Well, you'd probably still get from high end gear what you get when doing a low level dungeon in endgame gear -- it will at least get you to the stat cap (for that duty), which makes it a lot easier than when you're at the minimum entry requirements.

I would actually be for more encounters being a lot more strategic, and not in the "follow this strategy = win" kind of way. (And without the 'fail to dodge this even once = lose' mechanics)... That would be really neat^^