No.
I would make an exception if the current paradigm changed. ie currently: +2s = widespread availability, and assumed gear, +3s = grind in 20 completions of an easy raid (I'm looking at you, shroud), and +4s = hyper rare. If the level cap were raising and +4 tomes were to become more available, with +5s being the new hard to get tomes, then i'd be ok with seeing +3s in store as a "catch up to the minimum standard for hardcore raiding".