I should mention, something like straight stifles, don't seem to be a major fault in the show ring. Europe's world champion Tosa for 2006 and 2008 (not 100% sure on the years, but recent), has pretty well dead straight stifles. And probably the most extreme molosser, the EB, tends to have very little angulation as far as I can remember (goes for my own EB). It is really hard to tell how much better a given dog would do at it's job, if it had "perfect" angulation. I also think it's more to do with physical conditioning and "heart". My EB runs quite quickly for a stumpy little thing, jumps straight up in the air sometimes 4' high, and when she was a young dog, she was hell to hold back if pulling at the leash. !teeth