So I was just watching Holmes on Homes, and they were showing a quick close-up of cutting a 2x4, making two passes, cutting the top half first, then finishing it off: http://www.youtube.com/watch?v=vLyUzoPXXsk
I've never seen (or at least noticed) anyone do it this way before, nor can I find any info on it. I usually just cut straight down, or go across the whole board in one pass. Is there some benefit to doing it this way? What's the "proper" way to cut through dimensional lumber?