There's another problem with this plan, though. Unless they remove the current stones and oils, progression-oriented raiders are going to be running back to Outland and farming up the mats for old stones and oils all the time. This is nothing new really; dedicated raiders have been going to great lengths for buffs since the days of mind-controlling fire resistance off UBRS mobs to go to MC and BWL. Still, I don't think it's what Blizz had in mind in removing them, so my bet is that old stones/oils will either be removed, or prevented from working on players over level 70 (like the Riding Crop).
Update: Looks like they went the latter route. Stones/oils will not work on post-70 items.