Could absolutely be done, the xp seems to scale somewhat. I mean you won't get 168k per battle as you would at 89th lvl, but fighting a high lvl team gives nicer xp and if you have heirlooms it could be quite a lot of xp. The safest place is probably the heartlands in valley of four winds - there's not a lot of mobs around if you know where to avoid, nearby town and many pets to fight. Getting there can be an issue, unless you have a friend with a passenger flyer. That or just outside of your faction HQ in vale of eternal blossoms around the lakes. Though that may change quite a bit in the next patch.
That's actually a really good idea, once the character xp bug is fixed I think I'll try this. Thank you very much for this idea, I hadn't considered this and it seems like a fun 'challenge' in alt leveling. I'll have to make an alt for this to complement my gathering only for xp alt.