The left pipeline is +2 latency due to regrabbing once at the start, and then an air. That sucks.

Eliminating the second regrab seems viable. Eliminating the first is much harder. That would get 24.

But it would be faster to build the last product by pulling off a fresh input and rejecting quicksilver from it. I decided not to do that and look forward to seeing the work of the madwoman who did.