While leveling, can the very best prot warriors hold aggro on the very best aoe dps?

Curious about theoretical top of the line performance. If you have a prot warrior who knows all the tricks, spams battleshout rather than demo shout, uses revenge off of cooldown, etc. Can the strongest dps classes in the game still pull aggro off of them?I guess what I'm trying to ask is, if I lose aggro at all as a tank, is it always my fault? Because I recently learned some new tricks for holding aggro better, and I wanna put that to the test and see if I can improve.