I'm a new warrior but all I do Is
Shock wave (after I have moved back a little)
Then normal rotation
I haven't lost threat yet and I only taunt if heroic throw is on cd I throw intercept and heroic leap into the mix of I missed a second caster. If I see a mob running to healer I intervene to healer (focus intervene macro) and grab mob on the way back to the rest.
I use tc as my first hit because it's an aoe and gets some initial threat shock wave to stun them and rend tc while they are stunned. tc on cd and shock wave at 3 stacks.
Hope that helped but that just my experience.