Hmmm? Virtually all of us leveled 70-80 and I don't really remember ever getting 0 xp for 2 hours. And I did it 90% via questing, I did run instances a bit but after 2-3 instance runs I would get bored silly and have to go out and quest.

I agree the questing in WOTLK sucks for multiboxers (BUT IS AWESOME for single boxers esp/ with all the "flavor"), since it involves so many collections. Once you do unlock a quest hub via collections though there are going to be quite a few kill type quests. What I suggest is not using something like Questhelper/Carbonite, since it will recommend doing everything, but instead use Wowhead to figure out which quests open up quest hubs, do those, then only do the quests that are kill.

Nonetheless it is painful, and I always wonder about people with multiple teams. After having done it once, I am not going to level another team to 80 (even though I have like 12+ 60s laying around) again until Blizzard fixes the collection issues, doing it solo for future characters is much more enjoyable, esp if you have 1-2 of your 80 guys follow out-of-party and just heal/dps the tagged mobs.