Yifu was specifically interested in identifying in pinning individual identification meta-data to that which exists in the blockchain as I recall things.


We've been through this years ago.  Of course you taint UTXO's and summate them to characterize a wallet (as if it matters.)  It's not only possible to have a percent taint, it's relatively trivial.  It's also fairly trivial to associate UTXO's to other metadata and flags.  That would be the heart of a validation service, and it is very far from rocket science.

You are trying to say that Bitcoin has no scaling problems and because there is no danger of to many UTXO's (which pretty much will always need to be in fast access (which is, parenthetically, a long ago solved problem for large players who operate football field sized datacenters)) and at the same time that the UTXO set is so complex that they could not be analyzed even though the entire system is highly deterministic.  Which is it, bro?

People who use multibit-type clients will probably not even know any difference.  Let the server to the heavy lifting.  Just push the 'upgrade' button and a nice little 'percent taint' is a new addition which rapidly becomes one more feature.  The handful of ancient dinosaurs who run a full node can easily check transactions against my government chartered service as needed.  In fact, for PR reasons, I'll even make this free.  This will allow folks to call Bitcoin a 'peer-2-peer' system if they can stifle a chuckle when doing so.