I've found that the reason why people don't adapt to certain failure of mechanics or deaths of certain DPS or one tank, is that people just give up.

I know that as a healer for our FCoB, when a death happens at a bad part, our DPS lose focus and the WHM in my group becomes scatter-brained. I'm not even sure why that is because these fights are more forgiving in getting back up on your feet than the SCoB that came before it.

For us, one time that actually happened...

T11, tethers. Something happened and two groups just failed at it really hard. Our WHM was losing it MP wise, did a raise and went to helping tanks, and I just decided that I didn't feel like raising three other people. So I just WHM LB3'd and we finished the fight just fine with a Protect back up. Our DPS was strong enough that we made it before enrage.

With T10 charges, if too many people get hit by the heat lightning, just let the one person die. Better than having multiple die.

T12? Our group finds this turn so easy so we've never had any problems.

T13? Well...any death, I just end up smacking the WHM upside the head.