How do you deal with sluggish tanks?

[Leonus]

Play a tank if you want to set the pace.

Tanks really only control the downtime pace.

Dps control the uptime pace because they're really the ones killing stuff.

Tanks aren't controlling how fast I kill stuff, just how fast they pull said stuff. I just don't like the downtime. Sometimes reasons are pretty legit, but a lot of the cooldown aren't really needed for dungeons.

Also, I never really understood why everyone assumes tanks have to be the leader. Anyone is capable of doing it honestly. Just because the tank's job is to take a beating doesn't mean they have to be the leader.

Edit: I actually find it more annoying when tanks pull when I'm not ready.