No.
About a year ago, I had a student who could not get his gun to go into battery after pulling back and releasing. After some examination and discussion, it became obvious that the buffer was causing the problem.
This caused more thought and has resulted in my opinion that a buffer is DANGEROUS. If the buffer prevents the full rearward motion of the slide relative to the frame, it is also preventing the full opening of the ejection port (specifcally because of the movement of the slide relative to the barrel, which is connected to the frame) and the full intended force of the ejector against the rear of the case... both of these can cause reliability issues. In the former case, a FTF round may not eject reliably resulting in a double feed or stovepipe..... in the later any round may not be completely cast out of the way of the slide as it returns forward resulting in a stovepipe.
I have never been convinced that they are a necessary thing, but since it has become obvious that they cause real problems, I suggest to students and anyone else who asks that they take them out immediately.
The original problem was caused by the lack of complete rearward travel which meant that the slide was not fully pushing the slide-release down out of the way.
Of course, as these things work, now that I know what to look for, I have seen the problems several times.
-RJP