How to raise expertise as tank or do I need to

[Borstad]

I applyed to a guild on my server and one of their proc warriors looked me over and said i need more expertise to tank for people pulling 4-5k in raid.
I never have had a problem with threat with the simple prority lit of s&b sheild slam, revenge, shield slam and devestate.
I usally put vigilance on a warlock or high aggro dpser such as an arms warrior to up the amount of threat I create.
I create an average of 4k-6k tps based on how many buffs I have.
Should I worry about adding more expertise or am I fine the way I am?
Also, if I need to add expertise, where can I gem for it and any sidegrades/upgrades I could get to help?

[Wars]

Log out in tank gear please. If you're over 26 expertise then you're fine. Between 20-26 and I would sub in a stam/expertise gem where I could, other than that, you should be fine. If you're somehow under 20 expertise, then you need to get more.

[Borstad]

Thanks sorry about not being in tank gear I got dced with arms gear on and forgot about it.