A well written Tumbler wouldn’t connect any of your money to your own wallets, it’s not hard to think how an algorithm would do this. Just keep an internal ledger and make sure the money doesn’t come back to the source.

Ross probably could’ve even made his own tumbler. Giving out his money to anyone that sends him some would be a naive way to think about it.

In terms of amount, I don’t think it would be hard with all the illicit activity on bitcoin to launder even this amount of money, but it’s not like he would need all of it right away.

Anyways, this is in response to “isn’t this a public ledger?” To which the answer is, “not if you make part of the ledger private—outside the blockchain—it isn’t.”