Not sure if your rotation here is meant for multiple mobs like a trash pull or a single target.
In any case, as the above poster said, Devestate is a low priority skill and does not account for as much threat as Shield Slam and Revenge. It is important and should be used.
Warrior tanks don't have a rotation so much anymore as a heirarchy of skills based upon priority. To secure maximum threat on a single target, I suggest the following:
Charge->Shield Slam-> Revenge->Concussion Blow/Shockwave-> Devestate.
The key is converting as many 'next swing' attacks into Heroic Strikes as possible, given a high level of rage which in the game currently, is much of the time, especially on single targets. Shield Slam and Revenge are mandatory as often as possible. TC is not very helpful on single targets, more of a debuff applier than a threat skill.
For multiple mobs:
Charge-> SS-> TC-> Shockwave- Cleave/TC/SW spam. Tab target and use high threat moves like SS/Rev to build up more threat.
Aside from mechanics, I find that being aggressive is critical to success, especially on trash tanking. Get into the mobs and begin your threat rotation and seize time away from the DPS. If you shoot pull and let mobs run back to you or wait for every DPSer to poise their fingers over their nuke key, you're asking for trouble. If you can buy an extra TC or cleave or 2 while DPS is looting, drinking, replying to tells, whatever, you have a better lead on threat and can give yourself a little breathing room.
your hat may be nice, but I have the little white tank top that says Legendary right across my boobs. I win. (or more correctly, H wins)