I don' t think twisting stuff up to get 65 pounds would hurt the bow either. Problem is what Joe points out. If you twist up the string to keep the same draw length, you also increase brace height. Higher brace height = less power stroke for a given draw. Less power stroke = less stored energy. Less stored energy = less speed and KE. It' s possible you could pick up a little bit of speed right before you hit the point of diminishing returns, but in my experiments I' ve never seen enough speed gain to keep pushing the bow past it' s design limit.
Now, quieter shooting, less vibration and more forgiveness... Those are the reasons I push the pre-stress on my bows a bit. When you' ve got ' em wound up tight, they sure don' t do a lot of vibrating.
