My sister killed her first deer (150# doe) with 37# and 24" draw. There is a woman in our club who shoots about 42# and 23" draw and gets complete passthroughs. The trick is to get the arrow flying as true as possible, use a good sharp broadhea, and limit the length of your shots. With 50# that means pretty much 30 yards max, which is going to end up being 90% of all shots at whitetails anyway.

You can do your homework and find that people still kill deer with 35# recurves which don't generate anything close to a 50# compound for energy. It's all in arrow flight and arrow placement.