Tank and Healer here too.

A proper tank will always check if others are capable of speed running and will also test an unknown healer in a smaller pull before going berserk.
I have never wiped in a speedrun when tanking. I rotate CD's, pop multiple when taking too much damage and make certain the healer is near me when starting the run.

I did a 15 min Amdapor Keep(HM) run the other day with 3 FC mates, it was a complete mob massacre. Granted it was a premade group in which we know eachothers' playstyles and knew we could rely on eachother.

As WHM I always assume the worst of DF tanks, I'll assume they are complete morons which do not know how to hold aggro nor how to use CD's. This way I am always prepared for what gets thrown at me. Start with Divine Seal + Regen, Eye for an Eye and then spam Cure 1/Cure 2 to keep him up. If tank really goes low health on the initial pull I might use benediction to buy me a few seconds to start the heal spam