I'm completely confused about how sunder/devastate glyphs work in regards to threat. I've read posts saying that the second applied sunder just gives the effect, but no additional threat; then one saying it does.
I'm inclined to say it does, as well as generate a TON of threat initially.
Example. I MT for our guild. We are on the phase one of KT. Abombs start coming in, I charge in (of course while they are in safe range) SS off the bat, etc. The OT comes waltzing over, devastates (maxing it out by this point) and guess who has aggro? The OT. i even checked to see if he was being a sneaky bastard and put a Vig on me for funsies, but nope. The only time i managed to keep it for myself was if my SS crit.
So after the raid i check his spec: 13/3/55. his meta is the 32stam/2%armor. he glyphs sunder, devastate, revenge.