Radical thought...remove the off-tank?

[Dzian]

There are so many different ways to make 2 tanks required. Putting a debuff on a tank to force a swap is the laziest.

Yes but alot of stuff is lazy by design every encounter is so heavily scripted it's gets to a point you could almost automate your cooldowns. 45 seconds into fight pop cool down. 90 seconds. Pop cool down. Etc etc. There's never any variance...

That also makes for uninteresting tank swaps because there's never a situation where a tank has had to use all his cooldowns in a random 30 second burst and then swap out because he has none left or anything such. Where currently most swaps are because of those arbitary vulnerability things.