Moreover, and probably worse, each specific configuration increases the distance between your daily Vim-fu and the one you'll have to use on another user or another machine. And these occasions have been, in my experience, those when great Vim-fu was the most critical (eg. trying to keep your hand on a dying server on a flooded connection, or showing off your skills on your boss's Mac during plane trip). All this holds for bashrc too. The closest to the default is the best, to some extent.
I take vimrc posts as good occasions to proofread mine and remove all unused stuff. I just commented out a very weird "set notagbsearch" which was probably killing my <ctrl>-].