Straightarrow, I didn't say that you said this or even suggested it. I said that the logic you and Artur are using when applied to the rectangle results in this conclusion. And it does!
I wasn't offended, but my logic isn't anywhere near your portrayal. My logic showed how I could decrease KE and yet increase penetration potential in a live animal by increasing momentum. This is 6 million miles (no exageration) from what you suggested. Responding to my assertion by giving an example that is competely and totally unlike what we're talking about, is a cheap shot.