info-mac@uw-beaver (info-mac) (09/01/84)
From: Tim McNerney <TIM@MIT-MC> Two flaws in your analysis: (1) You are completely ignoring padding, which makes the character by character comparison invalid, and (2) for editors like Emacs, scroll region is much more desirable because it does not affect the mode line at the bottom of the screen, whereas insert and delete line commands "jiggle" the mode line. Furthermore, editors often simulate scroll region by doing a move cursor, delete line, move cursor, insert line, so scroll region is an optimization.