While I guess you might not benefit from this tidbit if you have an escort, there's a place waaaaaaaay down at the bottom of Wintergrasp on the waterfall that you can get to if you fly up from Dragonblight. If you scoot scoot just so, you can be close enough to the water to be technically fishing in Wintergrasp, but are still in Dragonblight so that you aren't flagged and don't have to worry about getting killed as you fish :>

thanks for the tip! now i can go there to fish alone with my high level toons too!