> it's done by rebasing 'u' onto 's' and then rebasing 't' and 'v' onto the rebased 'u'. That sounds like 2 operations, not 1. I think that's why I was confus

> it's done by rebasing 'u' onto 's' and then rebasing 't' and 'v' onto the rebased 'u'. That sounds like 2 operations, not 1. I think that's why I was confused. The docs do clarify that there's an extra rebase going on though, so thanks! Yes, -d sounds like what I expected.