Originally Posted by Lucitron

While it is a good chance that Resto and Elemental Shamans will share the same armour pool, there should still be enchants and gems that covers the few missing spell-hit percents. Outside of that, then we have Rings, Amulets, Weapons and Off-hand items that can cover any potential loss. Heck, we can still wear cloth if necessary, and we should not forget a Moonkin with Imp. Faerie Fire.

In short, Elemental Oath is an interesting talent but I doubt it will be desireable in a PvE situation. If you want to reach the spell hit cap, then it should still be relative easy to do so.