EDIT: Disregard. Looks like I'm 2 for 2 today.

The post you responded to was dated 02/16/07. At that time, you COULD use flasks+potions together.

You may wish to expand your listing of items to include some blues, such as Steam-Hinge Chain of Valor, Sha'tari Vindicator's Waistguard, Ogri'la Aegis, stat enchants on rings, etc.

There might also be of some benefit to use dropdowns for easier selection, too. That'd let people more easily whittle down gear to what they have available and how close they can get with different socket usage. In general, 1-3% crushing is what most tanks currently experience.. Thus reaching 99-100% avoidance while maintaining 490 defense, reasonable armor and HP might be of some benefit too.

I'm normally a stamina/armor sort of tank, but a few weeks ago I put together a set for passive crush immunity vs dual wielders. I've been using this set on Prince in Karazhan and it seems to work pretty well.

Recently, I got both the void reaver bracres and the tempest keep trash ring, so I decided to see if I could make a passive crush immunity set for non-dual wielders. I ended up only 6% short, so that could be made up with raid buffs/debuffs. My rule has been that I won't sacrifice anything from my stamina/armor set by adding avoidance enchants or gems to that gear.

Does anyone find this sort of set useful in 25 man raids?

Might want to check [Warriors] Shield block rating, the topic was brought up there just recently.