> throw a beefy server at the list of transactions, and since you know how much money arrived in someone's possession on a given date, you can now trace it back

> throw a beefy server at the list of transactions, and since you know how much money arrived in someone's possession on a given date, you can now trace it backwards by crunching the numbers. I hope you realize that you haven't actually described a process for tracing Bitcoin transactions. You can't just take an arbitrary problem, say "throw a computer at it", and consider it solved. I don't mean to be abrasive, but you are clearly ignorant of the state of affairs of Bitcoin anonymity systems. Look up coinjoin, for starters. When you have highly-connected (in the graph sense), properly conducted mixing systems, you can't just "trace the transactions".