It is a question I have often wondered about but, yes, I think I am mostly interested in predicting draw weight. Normally I only worry about balanced limbs and good tiller with as little set as I can get. Then I string it and start worrying about weight. Up til now, a bow with excess draw weight has been a bonus but as my skiils improve I suddenly find my bows really heavy at brace and it would be good to predict a ball park draw weight without running to my pc and running a mass calculation