I like it!

The atomic swap to inside the channel seems like a useful rebalancing technique in general (though asking me late Saturday night it's possible I missed something!).  It's possibly more general than the thoughts I had for upgrading/changing anchors, but that requires more pondering.

It doubles the total opening time, which may or may not be a problem.  But outsourcability is so nice it's probably worth it!

Now please go back in time and post this last week, before I implement dual-anchors