Motor cooling

Astro's post re: Ninco Subaru got me thinking. I know, it doesn't happen very often! Quite a few motors come with stickers wrapped around them. The one's which concern me are the mabuchi ones such as those supplied in Pink Kar, and also the proslot evo range. The cans, as most of you know have 2 cooling slots (I presume that's what they are) on one side, running parallel to the armature. I usually cut the stickers away from these slots. Am I wasting my time or would it do some good say, in an endurance race?
I know the slots make it easy to spray lighter fluid in to clean the comm (hopefully)


Mark.