The XP values for the High Road on Heroic are not good. Compare it to similar level wilderness areas and you'll see that it is very undervalued. If you're going to shove quest chains inside of wilderness areas, you need to make sure both the quests and the wilderness areas are worth the effort. High Road isn't.
I've mentioned it before, but if necessary, I can repost the link that tells you how to determine XP. But please, stop pulling bad numbers out of your butts.