This is my introduction, see, I'm socialized! But seriously, I noticed that someone here quoted some of my theoretical work on the P/J difference, and I thought I might as well post a response...Which I may do, shortly. I hope necromancy isn't The Worst Thing Ever here!
I've done some very interesting work on 16-type, including, most importantly, a sociobiological theory of human polymorphism based on it. I call it "task theory" for short. We're like ants, but a little more complex. That's just the tip of the iceberg, quantitatively speaking.