I don't think string jumping is as much of an issue as people like to make it out to be. I think a lot of people like to use it as an excuse for just plain old missing, miss judging yardarge or pulling a shot.

The newer bows are plenty fast and quiet enough that it shouldn't be an issue. Bottom line is learn deer body language and don't shoot at alert deer. If you shoot a relaxed deer that isn't looking right at you the chances are really high the arrow will be in the dirt on the other side of the deer before it knows what happened. I find it hard to believe that a deer can hear something, react and be out of the way in a blink of an eye.

I don't remember where I read it, but some engineer or something did the math. In order for a deer to really jump the string after you shoot it's feet would have to leave the ground while it was going down, or be attached to the ground. It was physically impossible for it to move that fast in a downward motion and stay planted. It defies the laws of gravity.

I however have seen the video of them moving on the shot. These critters are amazingly weary and fast.

I don't believe the speed differences you are talking about would make any difference at all to the deer. They would help with the yardage however. You could be a bit off on your estimation and hit closer to your mark than with a slower bow.

Paul