The simple fact of the matter is that most of the raiders like REing because of how poorly gear is itemized. If they itemize everything to be BiS without swapping mods I'm all for making it impossible to learn, but ONLY if they do that.
It's not as if the only options are "nothing can be REd for schemas" and "everything can be REd for schemas". Back in ye olden days, when KP and EV were the only thing around, you could craft the mods and enhs assuming you got lucky and the actual legit schema dropped. The items themselves could be made, but the only people that *could* make them were raiders and the only way to get the mats (for the good stuff) was by *actually raiding* (and most guilds had Alien Data Cubes coming out of a number of orifices and still do). The only problem was that the schematics were, honestly, *way* too rare. Fix that problem (by either giving the last bosses or two a guaranteed BoP enh or mod schema and the final boss a chance a random armoring/hilt schema or all bosses growing chance at dropping one of the schemas), and I doubt anyone would have any issue. You can have both exclusivity *and* crafting gear, and it's not even all that hard.