What is the pace for a heroic?

I don't generally like tanking all that often. It's fun to do every once in a while, and I'm pretty decent at it now, but i'm never quite sure how fast to go. Honestly, healer's mana and rune cool downs provided I'd chain pull instances without skipping a beat but that's stressful for no reason. I methodically pull. Maybe I wait a little too long between pulls (I feel like it's maybe a solid 4 or 5 seconds after a pull finishes before I even start moving again). What I'm trying to say, is that I treat each pull as an encounter, and make sure everyones mentally ready for it, but it's kind of at a walkers pace when I could easily jog.

As a side note, most of my waiting time after pulls is to allowed death and decay to come off cool down, or to refresh bone shield and then wait for rune to pop up again. I think I might fair better with another class who is more instanteous. Runes and staggered enemies are infuriating. Only thing I REALLY like about tanking with my death knight, is that positioning and caster aggro is a breeze to manage.