The Tokyo whale has said that he sells with the aid of an exchange but in a way that shouldn't affect the market price. So some form of OTC or private sale brokered by the exchange? I guess if there's someone who wants to buy substantial amounts without moving the price up they could tie up.
Unfortunately even moving the money out of the GOX wallets now will be enough to trigger a market fall, particularly in a jittery bear market.
Yea it seems any movement from the can cause a ruckus. The maturity of the markets need to catch up to the price or else we are doomed.