The theory is that as long as the arrow is on the string, your grip/follow through will affect the flight. I say theory because I have never read about any experiment that proved this true.
I find that I always shoot well when my form is good. When my form gets lazy, I'm inconsistent. All of my bows have brace heights on the large side (7 5/8" - 8 1/4"

. The 8 1/4" is my target bow which is the one I shoot most consistently well.
Check out what the best target archers are shooting. These folks have perfected their form. Most use bows that are longer axle to axle and have generous brace heights.