As tank, Provoke macros are useless for tank swaps. Believe it or not, tanks don't need Provoke macros. When it's time to swap, I just stop attacking. I don't have to watch for when to stop, I just stop. It's not that hard. Tank swap is a collaborative process, any tank that keeps munching their buttons when another tank is trying to take over, should go L2P.

Provoke macros are more useful to healers than to tanks, who may find it useful to get a note that someone's taking over the boss.