"When people say EH is the only important stat on tanks right now, they mean stacking stamina over avoidance (not armor). The article hasn't really shown why this isn't true or why it won't be true in ICC either. "

You're missing the point. No one is saying effective health isn't a valid number to look at. There are many valuable discussions to be had over the relative benefit of avoidance vs. mitigation vs. raw health.

The problem is that on the official tanking forums, no one ever mentions anything EXCEPT effective health. Avoidance, Cooldowns, Buffs/Debuffs, and most importantly Player Skill are never factored into peoples' complaints. They simply say "In BiS gear, a bear has 12% higher effective health than a warrior. NERF BEARS!" when that clearly is not a solution, and more importantly is not really even a problem to begin with!

Encounter design nowadays is very different than it used to be, and effective health is no longer the measure of tank survivability. Cooldowns, healer composition, and player skill are responsible for deaths far more often than a simple lack of effective health. The tanking forums have gotten so bad that most of the best tanks in the world simply don't get involved anymore. But if you ask them, you will find that all of them carry around lots of different gear and will change it depending on the situation.

Tanking lots of AoE trash? High avoidance, high block value.
Anub Adds? Passively unhittable, high block value, glyphed for Holy Wrath
Gormok? Stam, stam, stam.
Sarth 3D? Glyphed for Shield Wall and Last Stand, Pain Sup/Hand of Sacrifice requests

None of those encounters require high effective health. Gormok comes closest, but again, a huge part of that damage is unmitigatable, and an even larger part is unavoidable. If the official forums would simply recognize all of this, there could finally be some useful discussion, but as it stands, every thread degenerates into "I died because my EH was low. BUFF ME!"