I've never thought of doing this!

[crowdx]

So the real question is, does it check the gear you have currently OR does it check for the blizzard equivelent of GS and checks what the highest you have had for that toon?
If it is a simple case of checking your bags and NOT your bank then we could all be running UK or the like every day for hours on end.
I know the second dungeon my sub 3.4k GS DK tank got was PoS

[Drommon]

I have my own guild and I am wondering if it checks my guild bank. I would just have my toons queue up in green gear. I would love to run random UK over and over.

Whups, I forgot... You cant put soulbound items in the guild bank. doh!

So I would imagine that the alogorithm looks at your soulbound items, where ever they are.

[Firstcow]

Why not leave the instance and queue again in 15 mins? That's what I do and I rarely get "instances I hate" 2-3 times in a row.