This seems to be his strategy, good ol' martingale:
Yes martingale will always work in the end if thry have enough balance to cover the lost. Like him in the current time holding 10 btc and start to play from small basebet sure will get some profit in the end. But the only problem is how long will he go for this or how much does he want to earn here? As long as there is no end he will be disadvantage here. Anyway congrats for him to have won big amount there. I was wondering who will go next
That guy is insane though