I'm afraid I started the debate. Prior to writing the original postI had occasion to discuss penetration of an arrow 5 different times (both in person and via threads). That is not a bad thing. In fact it is a good thing. To make a long story short, all five of the people referenced only kinetic energy. They also referred to it (KE) out of context. Thus the post. I'm new to forums, and I quickly learned that they (threads) tend to take on a life of their own. But I love to read them. There are lots of people on this site (and I am sure other sites as well) that know a LOT about archery. I have learned a lot of late, got a few members down right annoyed with me, exchanged a few ideas, it has been fun.