Can someone tell me if my thoughts are correct?

Here it goes: If he says that he traded all our BTCs at Bitcoinica, then the BTC address that the outgoing 18,000 BTCs would have gone out from would be the same, right? Or at least there will be very few, right?

For example: I had 34BTC on my address at bitmarket. He would had transferred that to his BTC account, then traded it out.. even if he used few different "wallets" or whatever..

IF this is correct.. then how come he won't give us the address, so we can check on blockchain all the BTC going out..?

Further to that.. because once he lost all the money it then became a ponzi scheme, where he would have to get new BTC coming in to give to people that withdrew their coins, would still have gone through the same address or a new address that he used for the ponzi part?

(if it doesn't make sense, just read it again slowly..)

Just trying to figure it out..