Rack thats exactly why most of the top tagret guys have 28" or less draw lengths
I am not saying that the amount of time an arrow stays on the string has no effect on accuracy, it is just not the only or main effect of brace height. As far as most top archers I am not sure, it could be because 28" is about the correct draw for the average male height? Most non pros are to long on there draw.
It has to do more with how long the arrow is on the string I believe
And I dont see how arrow weight effects the power stroke of a bow
A heavy arrow does not effect the power stroke, it does however stay on the string much longer than a lighter one. So if the amount of time an arrow stayed on the string was the most critical factor in forgiveness I would believe the top archers would shoot the lightest fasted rigs they can handle. I do not believe the top spot shooters do so.
I do not want to come across as stating these other factors you mentioned are not important. I do believe there are many many factors that effect the forgiveness of a bow. But as far as brace I believe the most important factor is the distance from the release point of the arrow from the string to the rest.
Than again I may be 100% wrong
[:-]