Not all bows change speed with let off differences. It depends on cam design I think. And like BG said, it's pretty minimal any way.

In all honesty what most of us found is that the quest for speed is futile to a point. I have done it as others have. We have played the game and know the results, you can listen to us, or try it for yourself any way. I was told not to worry about it but experimented anyway. I learned a lot, mostly that the other guys were right.

Even if you did everything listed here to gain speed the honest truth is I don't believe it would be enough to be perceptable. You would need a chronograph to tell the performance difference in most cases. Your pin settings would most likely remain the same at 20, 30 and possibly 40 yards. And you wouldn't gain enough down range energy that it would make a difference on a deer. And like said above, 1200 fps is about where you would need to be in order for a deer not hear you or the arrow. I have seen pictures of deer flinching and ducking a muzzle loader bullet!

A quiet bow and a relaxed deer are much better than a fast noisy bow any day.

Like BG said, I would work on learning to shoot better before I worried about how fast or slow my rig was. I feel more important than speed is how well the bow fits you and how forgiving it is to shoot. If making a change is going to effect how well you can shoot the bow, I wouldn't consider it. 5 inches at 20 yards is ok for a beginner, but I would strive for a little better. It will make you more confident when you are in the stand. And for the most part a slower bow is more accurate and forgiving to a point. It gives the arrow more time to recover and straighten out. That is why most target shooters do not worry about speed and use lower poundage bows. Of course they are shooting fixed distances though.

Here are some links for all kinds of information for you to read.

http://www.huntersfriend.com/bowselection.htm

http://www.thebowman.com/

http://www.bowhunting.net/bobragsdale/ragsdale.html

http://www.merlin-bows.co.uk/MASTERFRAMESET.htm

Not to mention going to Eastons web site and downloading the easton tuning guide.

Good luck,
Paul