Well I can't explain the next diff jump. I mean every ASIC on the market ROIs very very hard. Even S1. So who keeps adding power?
Might be ASIC companies that couldn't sell their gear like Spoondolies. Maybe even Black Arrow started mining with their X3. Some S2 were sold, some S1 and some SP-10 but they don't account for the upcoming 14-18% jump.