Thanks for that info. Can you tell me who is working on this? Any links to working docs/discussions/dev-lists? In my opinion, this is the last technological hurdle that Bitcoin needs to jump before it is ready to scale to widespread adoption - that's why I care about this issue a lot.
Pieter Wuille has been working on this. A mailing list email about this is here:
https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2017-May/014337.htmlWhat he has been working on is a way to do rolling UTXO set hashes so that the UTXO set can be committed to the blockchain to allow for UTXO set syncing. Once we figure that out, the rest is fairly trivial.