Maybe I'm slow, but 3 heroics in 1 hour?

I can do CoS and VH in an hour, but I can't think of a 3rd that I could finish in that same hour, even AN. Maybe ToC. But how are you able to do 3 full runs an hour? Not looting? Skipping as much trash as you can? I mean Solo, SURE, I've done some pretty quick heroics, but I think it's unreasonable for a boxer to be pumping out 3 heroics an hour consistently.