Supervisor insists on writing a manuscript, yet procrastinates on writing for years So my supervisor insisted on writing a manuscript himself (because he wants to submit the paper to a better journal), but constantly procrastinated on the task for one and a half years despite repeated reminders from me. The drafting of the manuscript was completed eventually and submitted to a journal, but I can't help feeling that this situation has caused me to lose a tremendous amount of trust in my supervisor. This stems from the repeated broken promises by him to complete drafting the manuscript after attending to whatever unrelated tasks he deemed a higher priority at that time. And as I said, this went on for 1.5 years until I started to lose my patience and complained to the dean. This loss of trust is also a major cause of a further breakdown in the relationship with my supervisor down the line (e.g. me pestering him on other tasks incessantly etc.,) among other problems. 

This is in the past and I will be graduating soon so it is now too late to change anything. But I now wonder if I should have acted any differently? Is it not that big of a deal for a supervisor to delay something for so long? I was concerned with being scooped, the delay affecting my cv post graduation, and other potential complications that may arise from such a delay. Did I make a mountain out of a molehill? If not, maybe I should have requested for a change of supervisor before things had gotten out of hand. At that time, I thought a change of supervisor was a huge decision but I now realize that the alternate path that I have treaded has become the death knell of my future academic career. 

Edit: I had actually prepared a draft manuscript way back before my supervisor decided and insisted on writing the manuscript himself because he wanted to submit to a better journal (believing his writing skills to be better, which may or may not be true but that is unimportant; for what it's worth, I have sole-authored publications before so my writing skills are at least satisfactory). 

Edit 2: The degree in question is a PhD but the publication was only just submitted on the eve of the submission of my thesis (~2 months before).
In my opinion, if your career is dependent on publication, which is most often true in academic settings, one should just "keep on writing" regardless of conditions. 

Due the time the superviser delayed the writing, if you would have parallely kept on updating the manuscript, two things would have happened.


Supervisor does not write: 
You would have your updated manuscript as a factual proof that you can manage to writ the manuscript by yourself. May be then supervisor may back down and allow you to writ the manuscript. This would be a very helpful exercise for you because writing is arguably the most important and challenging skill in academia. You would get an opportunity to improve your skills further through practice. In future, that would indeed would help in your career. 
Supervisor does write: 
Your parallel updating of manuscript would only accelerate the writing process. The supervisor may probably feel a sense of competition (!) and may do write the manuscript. 


Both cases would have been eventually beneficial for your career. So I would say just "keep on writing".