Tacking just ahead and to leeward of your competitor while heading upwind so they're on your hip. It's a tactic used quite often in monohull racing to force your opponent to tack away, since they can't live in your dirty air.

The problem with doing it in catamarans is that you have to initiate the tack so far ahead, you might as well cross and/or it gives your opponent an opportunity to pinch up out of your dirty air before you get going.

T-Hutch has been racing big multis (ESS) for a while. He knows better.