So whose "fault" is it? If Poloniex had never added ETC to the exchange, would the minority fork have died? It seems all but certain that if no exchange ever added it, it would have died.

Of course, Poloniex is making a ton of money off fees from ETC, especially due to the roller coaster trading. So it's in Poloniex's very clear best interest to add ETC. How could the majority ETHers have incentivized Poloniex (and all other exchanges, for that matter) not to add ETC?

Nice writeup, by the way.