Ive seen the dragon tanked far north 1 time and it was the mostly pointless, stupid and annoying way to do the fight. the dps are literally(not figuratively) running for over 30 seconds to be able to hit the boss, then 15-30 seconds to get to an add, it's just impractical. I think the problem here is it doesn't matter where you tank the dragon just stack the skeletons properly, so they compensate for it by tanking the dragon in a God awful place.