Have a question... Not as to what is better (I gave my opinion on that) rather I have just been thinking "why the different methodology" that leads to the straight up Str>Vit debate.

Every other MMORPG I have ever played had tanks looking at three things, usually in this order...
eHP (effective hitpoints)=aggro managment
Utility
DPS.

For those that may not have heard eHP (maybe mentioned earlier but a lot of pages here) before it is basically adding up you HP pool and static mitigation, here defense, (no avoidance or CDs) to figure out how much damage you are guaranteed to survive. I really haven't seen this addressed number wise and as a numbers driven kinda guy am curious how/when you know/prove you have the adequate eHP?