This looks like an end-game of any PoW based blockchain, because it has a heavy "hook" into the economy, and the economy favors scale. You can call it emergent centralization. Incidentally, Byteball moves in the opposite direction.
Very interesting post. In the case of a small group of miners, they has a lot of incentives to keep up the system. If they are not doing what they have to do, we change PoW and they lose all mining investments. I am quite sure they will do what they have supposed to do even with that emergent centralization.
In the case of a small group of witnesses... someone say I don't have to trust them. In fact, this is what I am doing: I don't care about witnesses selection.
Troll-mode: Choose them and advance few years to the future, please. I trust your choices since 25-dec-2016, and I think all actual bb users would if they were asked.
Of course, you can slice their head, and you have sucessfully decentralized a witness.
Looks like you are still trying to make fun of the phrase "decentralized witness". Maybe not the best way to say it, "independent witness" would sound better but I bet you understood it anyway.
Way better. I understand that you are now the center, but when you distribute the witnesses left, you will have moved the centers, no destroyed them. Decentralization means "without center", at least in theory.