Even a guy like satoshi could dump his 1mn coin stash in BTCC by buying 5-10 alts, and then buying BTCs.
You really are worried about this, aren't you?
No I'm not worried the least about satoshi moving his coins. He's not here to daytrade etc. I'm just saying how it could go down between BTC < alts > BTCC with alts as a vehicle, without even needing to pass through $$$.
What's bizarre is that you are adding an extra step. Say miners choose to fork to classic's 2MB, Core changes the PoW and lowers difficulty through their own hard fork... What's preventing an altcoin exchange from listing CoreCoins with all the other alts? (Your argument actually presupposes that they
do.) The step of buying some other crap just to buy CoreCoin doesn't make any sense, you'd just sell classic bitcoin for core bitcoin directly, no? No fiat/verification required.