I say no but at the same time I kind of look at it and wonder why it even matters. You get next to nothing from leveling through the expansion. Pretty much the real leveling occurs when you start getting renown at max. The rest is just busy work that really doesn't teach you anything unless you want to try all the cov abilities for a bit while you are in the zone. So I guess it would make sense for you to have to level at least once cleanly. Not to mention Blizzard probably wants people to see it once. But after that.. meh.. who cares. I only say no because I am a old head and prefer to have people level and flavor of the month that is already out of control would explode even further.