Honestly, I hold enmity just fine right now. I had problems before, when I was a fresh 70 and queued into a 70 dungeon with dpsers in full blues or half blue and half green. But now that I'm in mostly blue with some green, I have zero problems holding enmity. I do have to watch out for that one odd sam or rdm, but it's all worked out well so far. Sometimes, they do creep up but it's not something a DA+PS won't fix.

What I find annoying, sometimes, is when dps don't switch targets. I know they don't have to, and I should hold enmity on them all, but this becomes exceedingly difficult when there are many numbers of targets to keep track of.