I used to do the my ($n, $m, $o) = shift so often that I vigorously enforce always using @_ now in my code. Because without fail the one time I use shift, I end up adding a variable later.

Plus I get really annoyed with all the extra typing I have to do to convert it from one format to the other. I suppose I should create an emacs macro to do that for me...Its good to know that laziness does indeed support good habits. ;-)