Good job, really extensive and definitely a must-read for all tanking warriors aiming to do endgame content. I totally agree with you that 2H's and dual-wields should be left home when grouping in instances, tanking with shields is the "warrior way" after all. Not that Fury warriors can't tank, they still have good innate abilities for tanking much like druids have ok-ish innate abilities for healing even without talents in resto. But when it comes to seamless teamplay in difficult environments, focusing on main roles becomes more and more important, leaving little to no room for hybrid builds.
One little correction though, if I may. As of 1.9 paladins no longer have Seal of Fury, but got Righteous Fury instead. RF is a 30 min self buff that increases the threat of all holy damage done, thus acting pretty much like the seal used to. The difference is that bubble boys can now use a combat seal PAIRED with RF to make aggro management easier. With the old seal, you would've had to judge the seal first, then switch to a seal that does holy damage. Loladins have currently no snap-aggro skill, but are getting it in TBC; pulls up to 3 mobs away from target ally.