I'm not sure how it is now.. but my guild has actually done this, in the current world. There are certain camps where it is possible, and it is absolutely a viable leveling option. I didn't participate when my guild did it, as I don't enjoy that.. but they did gain exp at a level that was equal, if not a bit better, than what others were getting fate grinding at that time. Just like in the FFXI world though, some camps are better for this than others because of mob density, and it is important to keep a chain going. Here's a reddit thread to get you going:

http://www.reddit.com/r/ffxiv/comments/1mswm8/

Good luck finding people to do it with you.