Syncing the blockchain right now is CPU bound. I understand that a lot of the optimization work done on upstream bitcoin core has not made it down to zcashd yet, but even with these optimizations, a sync will still take a long time.
What would be the implications if zcashd imported blocks verifying only the PoW (instead of the full verification, which is very very slow), and used the checkpoints to verify it’s on the right chain?
This obviously reduces security, but can you quantify by how much? Will this be better than SPV-level security that bitcoin has?
I did some experiments skipping the verification, and the zcash blockchain imports in almost 1/3rd the time.