Breakfast Topic: What are your speed leveling secrets?

The pandas are all telling us to "slow down", but that's not what WoW is about for many players. Yes, there are those of you out there who do like to take things at a gentle pace, to soak up the views and the scenery, and to take your sweet old time to get to max level, if you even get there at all.

Naturally, there's nothing wrong with either approach, but what I'm interested in today is your speed leveling secrets. You know, the things where you head over to another area at a funny time. Do you quest in higher level zones or lower level ones? Which is faster? Because, honestly, I'm not sure. You get more XP in higher level zones, per mob, but you might die more too, so that slows you down. You can probably complete quests faster in lower level zones, but then everything awards less XP... swings and roundabouts, as we say over here.

And what else? Heirlooms are rather an obvious one, as is being in a guild over level six so you benefit from the perks, particularly Fast Track. Do you level characters so much that you even have a pre-set path or plan that you follow? Or even just areas that you seek out or avoid thanks to their fantastic or awful leveling experience? What are the fastest races to level, even? I reckon human has got to be up there among the fastest, of course we're really only talking start zones here, but it seemed super-quick to me. What do you think?