Sorry AnonyMint, but I think you either don't know what you are talking about or bring confusion on purpose. "preimage the entropy"? "can't be a preimage because every peer is racing to compute it"? What is that supposed to mean?

"I can choose a seed a priori"? I've just proven that this is impossible.

I don't think this will be a productive discussion until you educate yourself enough to understand the arguments. Visit the "preimage attack" wikipedia page that I've linked, play the little md5 seed game. It will help.