user14288: (One of the reasons for asking this question is that I thought that maybe some people needed some extra/other knowledge/insight in order for the Noble Eightfold Path to become more accessible to them.)
Not necessarily to be "better" in knowledge and understanding than the Buddha overall, but to have a better understanding or additional explicit knowledge of some things or see certain things in more detail or accuracy with regards to certain aspects about the way out of suffering, and that may also address particular, "extreme" types of ignorance, mental illness, psychosis.   
To be able to answer other questions related to the way out of suffering that the Buddha was never asked. 

user-1: Householder (my person "guesses" Upasaka already) Angus, interested,
- Namo tassa bhagavato arahato sammā-sambuddhassa -
To answer in short: Yes, it is possible for the individuals situation, that someone else then the Buddha offers the Dhamma in "better" ways that the Buddha could, yet it's nevertheless the Buddha that one would have met.
While surely there is no teacher more advanced then the Buddha himself right view is gained on two things, hearing the good teaching, and yoniso manasikara.
When one of it is not present, it would not work that it would arise. While it requires the Dhamma of the Noble Ones, Arahats, best formulated by the Buddha, it does not necessary require to be spoken by a Buddha, meaning that even a worldling could transmit it, if remembering it, heard before.
It also does not require to be 1:1 a repetition of what the Buddha said, since, as he told, "what ever good told, is the word of the Tathagata.

...“But is this Ven. Uttara's own extemporaneous invention, or is it the saying of the Blessed One, the Worthy One, the Rightly Self-awakened One?”
“Very well, then, deva-king, I will give you an analogy, for there are cases where it's through an analogy that observant people can understand the meaning of what is being said. Suppose that not far from a village or town there was a great pile of grain, from which a great crowd of people were carrying away grain on their bodies, on their heads, in their laps, or in their cupped hands. If someone were to approach that great crowd of people and ask them, 'From where are you carrying away grain?' answering in what way would that great crowd of people answer so as to be answering rightly?”
“Venerable sir, they would answer, 'We are carrying it from that great pile of grain,' so as to be answering rightly.”
“In the same way, deva-king, whatever is well said is all a saying of the Blessed One, the Worthy One, the Rightly Self-awakened One. Adopting it again & again from there do we & others speak.”...  - Uttara Sutta

In that sense, "is the teaching of a Buddha required?", if categorical answered, one needs to say "yes and no". While it might be said by one not at the stage of Buddhahood, it still would be the word of Buddha (awakened one).
Now in relation of proper attention. To be able to listen to someone requires certain Upanissaya (strong conditions). It might be, that out of inclination toward certain kind of people, one would be not able to listen to the Buddha himself, the kind of speech, not used to it, and so not lower ones position to be able to receive it and maintain proper attention. Even at the Buddhas time there have been many arising to path and fruits by listening to the Sanghas member, someone near and dear, in words used to.
So also in relation of ones own giving into, while hearing the Dhamma, it could be that another then the Buddha is the one able to offer so that one can receive.
People have certain Nissaya with each other, remember the many cases where the Buddha invested much effort to convince leaders of sects. The members would never have been able to escape from there certain relation. One they heard the Dhamma or approve from those thwy are bound to, they could and many ordained on the account of following their leader.
The same works today as well. As long leaders of bond groups are not turning toward the Buddha, Dhamma, Sangha, their folk would not pay much attention. That's for example one reason why there is still no Sangha in the West and dies of even in the most old countries since leaded by democracy, the opinion of the many folk, which has naturally less access to the Gems.
This being the reason, Upanissayapaccaya (strong condition causes), incl. people and food, here to mention, people need to meet the right group, the right teacher for them. Being the case, it's again not so that someone else then the Buddha speaks, althought another might utter, since who ever sees/hears the Dhamma, sees/hears the Tathagata.
And that is why one owes much to them, as actually living Buddha, Dhamma, Sangha next to them, once they could receive their gift.

Has done much

"Bhikkhus, these three persons have done much to a person. Which three? Bhikkhus, the person gone to whom this person takes refuge in the Enlightenment, in the Teaching and the Community of bhikkhus.

"Bhikkhus, the person gone to whom this person knows as it really is, this is unpleasant, this is the arising of unpleasantness, this is the cessation of unpleasantness and this is the path leading to the cessation of unpleasantness.
"Again, bhikkhus, the person gone to whom, this person destroys desires, releases the mind and released through wisdom, here and now abides having realized. Bhikkhus, these three persons have done much to this person.
"Bhikkhus, it is not possible that these three persons could be thoroughly repaid with gratitude, by this person revering him, attending on him, clasping hands towards him and honouring him with robes, morsel food, dwellings and medicinal requisites."

This is how people, even today, gain rightly their living Buddha, Dhamma and Sangha.
This here taught is the reason why may do not good, really not good, when approached by commentaries, later uttering, even taught here, when not just cited, and neglect them categorically, neglect the Elders and those with directer relation as well as their advice.
Nevertheless it's important to remark that there, on account what the Buddha specifically had taught, are two people who sander the Tathagata: "One who explains something further which does not require further explaining and one who does not explains something further, what requires further explaining." So even one who simply just recite the Buddhas words, could, on certain occasions, in certain situations, or in and of itself, slander the Tathagata with it. And also the other way around.
However, in relation of the message here given: "Today" there are many who like to neglect this fact, thinking they do not owe anybody something, where defilement argue it was by the Tripple Gems, not any particular person... that is not only an indicator that they haven't arrived at the path, a sign of ingratitude, but also of a lot of demerits, holding wrong views, possible even cut off in their self-over-estimation, having made themselves to islands, islands which are drifting out into the open sea and bound to sink for away form borderlands to the Noble Domain.
This here taught is the reason why may do not good, really not good, when approached by commentaries, later uttering, even taught here, when not just cited, and neglect them categorically, neglect the Elders and those with directer relation as well as their advice.
A possible extended and improved answer, as well as given space to give into, how ever one feels inspired, can be found, also open for discussion, here: [Q&A] Could someone teach the Dhamma better then the Buddha?
(Note that this gift of Dhamma is not dedicated for trade, exchange, stacks or entertainment but as a means to make merits toward release from this wheel)

user111: The Buddha is omniscient. His knowledge is unobstructed. There is no knowledge that is hidden to him once he sets his mind on the subject. The Buddha has no peer except other Sammasambuddha in the past. So what you are saying is technically not possible.

user43: Obviously as with any non-trivial teaching or practice there is infinite amount of real life situations, and infinite amount of mistakes the students can make.
So while Dharma was presented both in summary and in details by the Buddha, there is always room for explanations about how this teaching should be applied in practical situations, and how to differentiate between mistaken understanding and valid understanding of the teaching.

user471: In the parable of the Simsapa leaves in SN 56.31, the Buddha took some Simsapa (Indian rosewood) leaves in his hand and said that the leaves in his hand were far less in number than the leaves in the forest. Similarly, he had realized far more than he taught. However, that which he taught is all that is needed for the path to end suffering. That which he did not teach is not relevant to the path to end suffering.
Meanwhile, in DN 16, he declared that he did not hide (in a "closed fist") any teachings from his disciples. He said he did not separate some teachings as being exotic or esoteric.
Based on these statements, we can say that more details regarding the path is unnecessary. Also, since the Shakyamuni Buddha was the last Sammasambuddha (or Buddha with full perfection), it is unlikely that anyone else coming after him would know more of the path than he does, unless they too achieve the same level of perfection.
Hence, it is plausible that primarily relying on the Buddha's original words (Buddhavacana or the Buddha's Words) in most of the Sutta Pitaka (and the corresponding Mahayana Agamas) is sufficient for understanding his teachings and the path. I say "most", because there are parts of the Sutta Pitaka which contain teachings or writings from other people e.g. Sariputta, Ananda, Mogallana, elder monks, elder nuns, a few advanced householders etc. Some parts of the Sutta Pitaka like some books in the Khuddaka Nikaya even come from later periods, like the Milindapanha. You can find more scholarly information on the authenticity of the Buddha's original words in the book "The Authenticity of the Early Buddhist Texts" by Bhikkhu Sujato and Bhikkhu Brahmali.
But this does not mean that it's wrong to elaborate or expand on the Buddha's teachings, while not contradicting the original teachings. In fact, I think teachers over the ages would definitely try to explain the teachings using new methods and analogies. However, such elaborations or expansions should be considered secondary sources, which are less important compared to the Buddha's original teachings.
Many traditional Theravadins say that the Abhidhamma was taught by the Buddha, but academic scholars say that this is a later work by disciples. To me, I would consider the Abhidhamma as a secondary source, that explains the Buddha's original teachings in the Sutta Pitaka. The many carefully collated lists in the Abhidhamma are useful.
The Visuddhimagga (or Path of Purification) written by Buddhaghosa in the 5th century in Sri Lanka is another useful secondary source that expands on Buddhist meditation practice and doctrine. It can be downloaded here.
Also many traditional Mahayanists say that the Mahayana sutras were taught by the Buddha in the second and third turning of the wheel, but academic scholars say that these are later works by Mahayana authors. To me, I would consider these as secondary sources too. Nagarjuna's Mūlamadhyamakakārikā contains an expansion on the Buddha's original definition of emptiness. I tried to analyze the link between Madhyamaka emptiness and Theravada emptiness in this question.
Of course, I understand that there will be traditional Theravadins and traditional Mahayanists who will disagree with some of my opinions above.

14288: <p>(One of the reasons for asking this question is that I thought that maybe some people needed some extra/other knowledge/insight in order for the Noble Eightfold Path to become more accessible to them.)</p>

<p>Not necessarily to be "better" in knowledge and understanding than the Buddha overall, but to have a better understanding or additional explicit knowledge of some things or see certain things in more detail or accuracy with regards to certain aspects about the way out of suffering, and that may also address particular, "extreme" types of ignorance, mental illness, psychosis.   </p>

<p>To be able to answer other questions related to the way out of suffering that the Buddha was never asked. </p>
 -1: <p>Householder (my person "guesses" Upasaka already) Angus, interested,</p>

<p><a href="http://zugangzureinsicht.org/html/homage_en.html" rel="nofollow noreferrer">- Namo tassa bhagavato arahato sammā-sambuddhassa -</a></p>

<p>To answer in short: <code>Yes, it is possible for the individuals situation, that someone else then the Buddha offers the Dhamma in "better" ways that the Buddha could, yet it's nevertheless the Buddha that one would have met.</code></p>

<p>While surely there is no teacher more advanced then the Buddha himself right view is gained on two things, hearing the good teaching, and <a href="http://accesstoinsight.eu/en/dictionary/yonisomanasikara" rel="nofollow noreferrer">yoniso manasikara</a>.</p>

<p>When one of it is not present, it would not work that it would arise. While it requires the Dhamma of the Noble Ones, Arahats, best formulated by the Buddha, it does not necessary require to be spoken by a Buddha, meaning that even a worldling could transmit it, if remembering it, heard before.</p>

<p>It also does not require to be 1:1 a repetition of what the Buddha said, since, as he told, "what ever good told, is the word of the Tathagata.</p>

<blockquote>
  <p>...“But is this Ven. Uttara's own extemporaneous invention, or is it the saying of the Blessed One, the Worthy One, the Rightly Self-awakened One?”</p>
  
  <p>“Very well, then, deva-king, I will give you an analogy, for there are cases where it's through an analogy that observant people can understand the meaning of what is being said. Suppose that not far from a village or town there was a great pile of grain, from which a great crowd of people were carrying away grain on their bodies, on their heads, in their laps, or in their cupped hands. If someone were to approach that great crowd of people and ask them, 'From where are you carrying away grain?' answering in what way would that great crowd of people answer so as to be answering rightly?”</p>
  
  <p>“Venerable sir, they would answer, 'We are carrying it from that great pile of grain,' so as to be answering rightly.”</p>
  
  <p>“In the same way, deva-king, whatever is well said is all a saying of the Blessed One, the Worthy One, the Rightly Self-awakened One. Adopting it again &amp; again from there do we &amp; others speak.”...  - <a href="http://accesstoinsight.eu/en/tipitaka/sut/an/an08/an08.008.than" rel="nofollow noreferrer">Uttara Sutta</a></p>
</blockquote>

<p>In that sense, "is the teaching of a Buddha required?", if categorical answered, one needs to say "yes and no". While it might be said by one not at the stage of Buddhahood, it still would be the word of Buddha (awakened one).</p>

<p>Now in relation of proper attention. To be able to listen to someone requires certain Upanissaya (strong conditions). It might be, that out of inclination toward certain kind of people, one would be not able to listen to the Buddha himself, the kind of speech, not used to it, and so not lower ones position to be able to receive it and maintain proper attention. Even at the Buddhas time there have been many arising to path and fruits by listening to the Sanghas member, someone near and dear, in words used to.</p>

<p>So also in relation of ones own giving into, while hearing the Dhamma, it could be that another then the Buddha is the one able to offer so that one can receive.</p>

<p>People have certain Nissaya with each other, remember the many cases where the Buddha invested much effort to convince leaders of sects. The members would never have been able to escape from there certain relation. One they heard the Dhamma or approve from those thwy are bound to, they could and many ordained on the account of following their leader.</p>

<p>The same works today as well. As long leaders of bond groups are not turning toward the Buddha, Dhamma, Sangha, their folk would not pay much attention. That's for example one reason why there is still no Sangha in the West and dies of even in the most old countries since leaded by democracy, the opinion of the many folk, which has naturally less access to the Gems.</p>

<p>This being the reason, Upanissayapaccaya (strong condition causes), incl. people and food, here to mention, people need to meet the right group, the right teacher for them. Being the case, it's again not so that someone else then the Buddha speaks, althought another might utter, since who ever sees/hears the Dhamma, sees/hears the Tathagata.</p>

<p>And that is why one owes much to them, as actually living Buddha, Dhamma, Sangha next to them, once they could receive their gift.</p>

<blockquote>
  <p><a href="http://sangham.net/index.php/page,s0402m2.mul2_en_uppa.html#an03.24" rel="nofollow noreferrer">Has done much</a></p>
  
  <ol start="24">
  <li>"Bhikkhus, these three persons have done much to a person. Which three? Bhikkhus, the person gone to whom this person takes refuge in the Enlightenment, in the Teaching and the Community of bhikkhus.</li>
  </ol>
  
  <p>"Bhikkhus, the person gone to whom this person knows as it really is, this is unpleasant, this is the arising of unpleasantness, this is the cessation of unpleasantness and this is the path leading to the cessation of unpleasantness.</p>
  
  <p>"Again, bhikkhus, the person gone to whom, this person destroys desires, releases the mind and released through wisdom, here and now abides having realized. Bhikkhus, these three persons have done much to this person.</p>
  
  <p>"Bhikkhus, it is not possible that these three persons could be thoroughly repaid with gratitude, by this person revering him, attending on him, clasping hands towards him and honouring him with robes, morsel food, dwellings and medicinal requisites."</p>
</blockquote>

<p>This is how people, even today, gain rightly their living Buddha, Dhamma and Sangha.</p>

<p>This here taught is the reason why may do not good, really not good, when approached by commentaries, later uttering, even taught here, when not just cited, and neglect them categorically, neglect the Elders and those with directer relation as well as their advice.</p>

<p>Nevertheless it's important to remark that there, on account what the Buddha specifically had taught, are two people who sander the Tathagata: "One who explains something further which does not require further explaining and one who does not explains something further, what requires further explaining." So even one who simply just recite the Buddhas words, could, on certain occasions, in certain situations, or in and of itself, slander the Tathagata with it. And also the other way around.</p>

<p>However, in relation of the message here given: "Today" there are many who like to neglect this fact, thinking they do not owe anybody something, where defilement argue it was by the Tripple Gems, not any particular person... that is not only an indicator that they haven't arrived at the path, a sign of ingratitude, but also of a lot of demerits, holding wrong views, possible even cut off in their self-over-estimation, having made themselves to islands, islands which are drifting out into the open sea and bound to sink for away form borderlands to the Noble Domain.</p>

<p>This here taught is the reason why may do not good, really not good, when approached by commentaries, later uttering, even taught here, when not just cited, and neglect them categorically, neglect the Elders and those with directer relation as well as their advice.</p>

<p>A possible extended and improved answer, as well as given space to give into, how ever one feels inspired, can be found, also open for discussion, here: <a href="http://sangham.net/index.php/topic,9348.msg19175.html#msg19175" rel="nofollow noreferrer">[Q&amp;A] Could someone teach the Dhamma better then the Buddha?</a></p>

<p><em>(Note that this gift of Dhamma is not dedicated for trade, exchange, stacks or entertainment but as a means to make merits toward release from this wheel)</em></p>
 111: <p>The Buddha is <a href="http://www.buddhanet.net/brahmaviharas/bvd073.htm" rel="nofollow noreferrer">omniscient</a>. His knowledge is unobstructed. There is no knowledge that is hidden to him once he sets his mind on the subject. The Buddha has no peer except other Sammasambuddha in the past. So what you are saying is technically not possible.</p>
 43: <p>Obviously as with any non-trivial teaching or practice there is infinite amount of real life situations, and infinite amount of mistakes the students can make.</p>

<p>So while Dharma was presented both in summary and in details by the Buddha, there is always room for explanations about how this teaching should be applied in practical situations, and how to differentiate between mistaken understanding and valid understanding of the teaching.</p>
 471: <p>In the parable of the Simsapa leaves in <a href="https://www.accesstoinsight.org/tipitaka/sn/sn56/sn56.031.than.html" rel="nofollow noreferrer">SN 56.31</a>, the Buddha took some Simsapa (Indian rosewood) leaves in his hand and said that the leaves in his hand were far less in number than the leaves in the forest. Similarly, he had realized far more than he taught. However, that which he taught is all that is needed for the path to end suffering. That which he did not teach is not relevant to the path to end suffering.</p>

<p>Meanwhile, in <a href="https://www.accesstoinsight.org/tipitaka/dn/dn.16.1-6.vaji.html" rel="nofollow noreferrer">DN 16</a>, he declared that he did not hide (in a "closed fist") any teachings from his disciples. He said he did not separate some teachings as being exotic or esoteric.</p>

<p>Based on these statements, we can say that more details regarding the path is unnecessary. Also, since the Shakyamuni Buddha was the last <a href="https://buddhism.stackexchange.com/q/20938/471">Sammasambuddha</a> (or Buddha with full perfection), it is unlikely that anyone else coming after him would know more of the path than he does, unless they too achieve the same level of perfection.</p>

<p>Hence, it is plausible that primarily relying on the Buddha's original words (<a href="https://en.wikipedia.org/wiki/Buddhavacana" rel="nofollow noreferrer">Buddhavacana</a> or the Buddha's Words) in most of the <a href="https://www.accesstoinsight.org/tipitaka/sutta.html" rel="nofollow noreferrer">Sutta Pitaka</a> (and the corresponding Mahayana Agamas) is sufficient for understanding his teachings and the path. I say "most", because there are parts of the <a href="https://www.accesstoinsight.org/tipitaka/sutta.html" rel="nofollow noreferrer">Sutta Pitaka</a> which contain teachings or writings from other people e.g. <a href="https://en.wikipedia.org/wiki/Sariputta" rel="nofollow noreferrer">Sariputta</a>, <a href="https://en.wikipedia.org/wiki/%C4%80nanda" rel="nofollow noreferrer">Ananda</a>, <a href="https://en.wikipedia.org/wiki/Maudgalyayana" rel="nofollow noreferrer">Mogallana</a>, elder monks, elder nuns, a few advanced householders etc. Some parts of the Sutta Pitaka like some books in the Khuddaka Nikaya even come from later periods, like the Milindapanha. You can find more scholarly information on the authenticity of the Buddha's original words in the book "<a href="https://ocbs.org/wp-content/uploads/2015/09/authenticity.pdf" rel="nofollow noreferrer">The Authenticity of the Early Buddhist Texts</a>" by Bhikkhu Sujato and Bhikkhu Brahmali.</p>

<p>But this does not mean that it's wrong to elaborate or expand on the Buddha's teachings, while not contradicting the original teachings. In fact, I think teachers over the ages would definitely try to explain the teachings using new methods and analogies. However, such elaborations or expansions should be considered secondary sources, which are less important compared to the Buddha's original teachings.</p>

<p>Many traditional Theravadins say that the <a href="https://en.wikipedia.org/wiki/Abhidhamma_Pitaka" rel="nofollow noreferrer">Abhidhamma</a> was taught by the Buddha, but academic scholars say that this is a later work by disciples. To me, I would consider the Abhidhamma as a secondary source, that explains the Buddha's original teachings in the Sutta Pitaka. The many carefully collated lists in the Abhidhamma are useful.</p>

<p>The <a href="https://en.wikipedia.org/wiki/Visuddhimagga" rel="nofollow noreferrer">Visuddhimagga</a> (or Path of Purification) written by Buddhaghosa in the 5th century in Sri Lanka is another useful secondary source that expands on Buddhist meditation practice and doctrine. It can be downloaded <a href="https://www.accesstoinsight.org/lib/authors/nanamoli/PathofPurification2011.pdf" rel="nofollow noreferrer">here</a>.</p>

<p>Also many traditional Mahayanists say that the <a href="https://en.wikipedia.org/wiki/Mahayana_sutras" rel="nofollow noreferrer">Mahayana sutras</a> were taught by the Buddha in the second and third turning of the wheel, but academic scholars say that these are later works by Mahayana authors. To me, I would consider these as secondary sources too. <a href="https://en.wikipedia.org/wiki/Nagarjuna" rel="nofollow noreferrer">Nagarjuna</a>'s <a href="https://en.wikipedia.org/wiki/M%C5%ABlamadhyamakak%C4%81rik%C4%81" rel="nofollow noreferrer">Mūlamadhyamakakārikā</a> contains an expansion on the Buddha's original definition of emptiness. I tried to analyze the link between Madhyamaka emptiness and Theravada emptiness in <a href="https://buddhism.stackexchange.com/q/28981/471">this question</a>.</p>

<p>Of course, I understand that there will be traditional Theravadins and traditional Mahayanists who will disagree with some of my opinions above.</p>
