Speaking at Comic Con in New York this week, Epic president Mike Capps explained that the chainsaw battles in Gears of War came about not through a lust for blood, but simply because the developers wanted you to actually see the game’s highly-detailed character models. From GameSpy:
It’s interesting the chainsaw ended up being pivotal to the Gears experience, given that Capps intimated that he was initially dismissive of the idea. “The reason [it] exists is because our characters are so bloody expensive to draw,” he said during the panel. What ultimately started off as a way to reconcile the relatively complex character models by forcing players into intimate contact with them (compare a close-up of a Locust grunt to, say, a Covenant Elite from Halo 3) ended up birthing the interactions that would come to define the game’s ferocious brand of combat.
Doesn’t sound as though there was too much more information given, according to that piece. Take a look anyway.