>And if you mix enough coins you can decrease the chances of being pinpointed exactly as the source, but you cannot definitively remove yourself from the bucket of suspects.
Not in my understanding. I have some coins X that are tainted. I send them to you, Y. You, Y, happen to have other coins completely unrelated to the address I sent my X coins to, and you send them to me at address Z. There's no blockchain link between X and Z.
I suppose physically tracking you down, assuming you keep logs, could hurt me, but if I trust you not to keep logs then I'm safe after you delete the logs.
