I'd be fine with this, if they made it so that you can only need on gear and you can't greed things for your other job. Or,

Let's say you are tanking as pld and drg gear drops and you greed it. And later you get some tank gear. Both your drg and your pld should now be loot locked to that instance of BCB. My point is you shouldn't be able to roll greed on gear on one job and then greed the same gear on another job. If you could FC's could abuse the system immensely.

E.g.

Your on BLM, FC runs you through you get all the drg gear that drops. Then you switch to Mnk and you get all the drg gear that drops. Then you switch to smn, then brd, etc. Then you save your DRG. FC runs it again this time your on DRG rolling on no gear while someone else rolls on everything for their Main role that drops via greed. FC's could gear out to average il80+ in one lockout. As long as everyone has all jobs to 50. And tbh, I've seen quite a lot of people with all jobs to 50.