user-1: I was reading about mindfulness here.  At the end I found this paragraph 

Let alone seven years, anyone who develops these four kinds of
  mindfulness meditation in this way for six years … five years … four
  years … three years … two years … one year … seven months … six months
  … five months … four months … three months … two months … one month …
  a fortnight … Let alone a fortnight, anyone who develops these four
  kinds of mindfulness meditation in this way for seven days can expect
  one of two results: enlightenment in the present life, or if there’s
  something left over, non-return.

Here Tathagata saying one keeping that kind of mindfulness for 7 days can get enlightenment? Is it exaggeration, translation problem or understanding problem or it's true? 

user10100: 
Is it exaggeration, translation problem or understanding problem or
  it's true?

The translation is fine, but the reader must know the environment and situation of that sutta, before read it. If the reader read it without the pre-required knowledge, it is the reader's fail.
The explanation
In atthakathā of MN 10 wrote:

Why Buddha taught mahāsatipaṭṭhānasutta to Kuru-people? Because they had enough ability to study the advance teaching. It's told that Kuru-people, such as bhikkhu, bhikkhunī, lay men, and lay women,  always had the potential body and the potential mind because Kuru-country had the richness of temperature, etc. Their potential body and potential mind supported their wisdom power, so they can studied  the advance teaching.

So, most Kuru-people were diṭṭhi-cārita, who have little dust in their eyes, according to netti desanāhāravibhaṅga.
The diṭṭhi-cārita people can attain jhāna easily. So they don't have to meditate jhāna because of their pure mind. They can enlighten at the listening moment. That's why in the end of mahāsatipaṭṭhānasutta's atthakathā wrote:

30,000 people enlightened as arahanta at the end of mahāsatipaṭṭhānasutta was taught.

therefore, the end of mahāsatipaṭṭhānasutta wrote:

Let alone seven years, anyone who develops these four kinds of mindfulness meditation in this way for six years … five years … four years … three years … two years … one year … seven months … six months … five months … four months … three months … two months … one month … a fortnight … Let alone a fortnight, anyone who develops these four kinds of mindfulness meditation in this way for seven days can expect one of two results: enlightenment in the present life, or if there’s something left over, non-return.

But for taṇhā-carita people,who have much dust in their eyes, they have to meditate jhāna, first. After they attained jhāna, they can count down for enlightenment like what buddha taught in the end of  mahāsatipaṭṭhānasutta. Because jhāna can pause their five hindrances, then their "dust in eyes" state will be same little  dust as diṭṭhi-carita and they are able to count down for enlightenment.

user2282: No exaggeration or translation problem here. A quick mundane analogy, say there's a complex quantum mechanics problem that needs to be solved, it'd be equally valid to say it could take seven years, or six years, or five years,... three months, two months, one months...or seven days for one to solve it. It all depends on where one is on the path of quantum mechanics. For a high school graduate, it sure would take at least seven years ( 4 years for a bachelor degree, 3-4 years for graduate degree), but for a professional physicist, seven days might be all s/he needs to crack it. 

-1: <p>I was reading about mindfulness <a href="https://suttacentral.net/mn10/en/sujato" rel="nofollow noreferrer">here</a>.  At the end I found this paragraph </p>

<blockquote>
  <p>Let alone seven years, anyone who develops these four kinds of
  mindfulness meditation in this way for six years … five years … four
  years … three years … two years … one year … seven months … six months
  … five months … four months … three months … two months … one month …
  a fortnight … <strong>Let alone a fortnight, anyone who develops these four
  kinds of mindfulness meditation in this way for seven days can expect
  one of two results: enlightenment in the present life, or if there’s
  something left over, non-return.</strong></p>
</blockquote>

<p>Here Tathagata saying one keeping that kind of mindfulness for 7 days can get enlightenment? Is it exaggeration, translation problem or understanding problem or it's true? </p>
 10100: <blockquote>
  <p>Is it exaggeration, translation problem or understanding problem or
  it's true?</p>
</blockquote>

<p>The translation is fine, but the reader must know the environment and situation of that sutta, before read it. If the reader read it without the pre-required knowledge, it is the reader's fail.</p>

<h2>The explanation</h2>

<p>In <a href="http://www.84000.org/tipitaka/atthapali/read_rm.php?B=5&amp;A=9140&amp;h=utusapp%C4%81y%C4%81disampannatt%C4%81" rel="nofollow noreferrer">atthakathā</a> of MN 10 wrote:</p>

<blockquote>
  <p>Why Buddha taught mahāsatipaṭṭhānasutta to Kuru-people? Because they had enough ability to study the advance teaching. It's told that Kuru-people, such as bhikkhu, bhikkhunī, lay men, and lay women,  always had the potential body and the potential mind because Kuru-country had the richness of temperature, etc. Their potential body and potential mind supported their wisdom power, so they can studied  the advance teaching.</p>
</blockquote>

<p>So, most Kuru-people were <a href="https://unmixedtheravada.blogspot.com/2018/05/a-lay-often-attach-5-strings-more-than.html" rel="nofollow noreferrer">diṭṭhi-cārita</a>, who <a href="http://www.84000.org/tipitaka/read/roman_read.php?B=15&amp;A=3906&amp;h=apparajakkhaj%C4%81tik%C4%81" rel="nofollow noreferrer">have little dust in their eyes</a>, according to netti <a href="http://tipitaka.wikia.com/wiki/Netti-Part-III.Chapter-i.16_Modes-Separate" rel="nofollow noreferrer">desanāhāravibhaṅga</a>.</p>

<p>The <a href="https://unmixedtheravada.blogspot.com/2018/05/a-lay-often-attach-5-strings-more-than.html" rel="nofollow noreferrer">diṭṭhi-cārita</a> people can attain jhāna easily. So they don't have to meditate jhāna because of their pure mind. They can enlighten at the listening moment. That's why in the end of mahāsatipaṭṭhānasutta's <a href="http://www.84000.org/tipitaka/atthapali/read_rm.php?B=5&amp;A=10809&amp;h=%20ti%E1%B9%83sabhikkhusahass%C4%81ni,arahatte,Mah%C4%81satipa%E1%B9%AD%E1%B9%ADh%C4%81nasuttava%E1%B9%87%E1%B9%87an%C4%81" rel="nofollow noreferrer">atthakathā</a> wrote:</p>

<blockquote>
  <p>30,000 people enlightened as arahanta at the end of mahāsatipaṭṭhānasutta was taught.</p>
</blockquote>

<p>therefore, the end of <a href="https://suttacentral.net/mn10/en/sujato" rel="nofollow noreferrer">mahāsatipaṭṭhānasutta</a> wrote:</p>

<blockquote>
  <p>Let alone seven years, anyone who develops these four kinds of mindfulness meditation in this way for six years … five years … four years … three years … two years … one year … seven months … six months … five months … four months … three months … two months … one month … a fortnight … Let alone a fortnight, anyone who develops these four kinds of mindfulness meditation in this way for seven days can expect one of two results: enlightenment in the present life, or if there’s something left over, non-return.</p>
</blockquote>

<p>But for <a href="https://unmixedtheravada.blogspot.com/2018/05/a-lay-often-attach-5-strings-more-than.html" rel="nofollow noreferrer">taṇhā-carita</a> people,who <a href="http://www.84000.org/tipitaka/read/roman_read.php?B=15&amp;A=3906&amp;h=apparajakkhaj%C4%81tik%C4%81" rel="nofollow noreferrer">have much dust in their eyes</a>, they have to meditate jhāna, first. After they attained jhāna, they can count down for enlightenment like what buddha taught in the end of  <a href="https://suttacentral.net/mn10/en/sujato" rel="nofollow noreferrer">mahāsatipaṭṭhānasutta</a>. <strong>Because jhāna can pause their five hindrances, then their "dust in eyes" state will be same little  dust as diṭṭhi-carita and they are able to count down for enlightenment.</strong></p>
 2282: <p>No exaggeration or translation problem here. A quick mundane analogy, say there's a complex quantum mechanics problem that needs to be solved, it'd be equally valid to say it could take seven years, or six years, or five years,... three months, two months, one months...or seven days for one to solve it. It all depends on where one is on the path of quantum mechanics. For a high school graduate, it sure would take at least seven years ( 4 years for a bachelor degree, 3-4 years for graduate degree), but for a professional physicist, seven days might be all s/he needs to crack it. </p>
