Three things that jump out at me right away as problematic with this thing (bearing in mind that the character I have in the game is a Holy priest, so the second effect is the one that applies).
1) It only works in 1 of the 3 healing chakras, which means that it simply fills a trinket slot and gives no benefit in either of the other two stances.
2) It affects a single-target healing spell, but only when you are in your multi-target healing stance.
3) It actually nerfs the spell. It is already our slowest heal, and this makes it take even longer to cast.
4) Bonus gripe: this is the weakest version of the trinket. The higher level versions make the spell take even longer, and cost even more mana to cast.
This thing is so bad, it's insulting. It kinda sums up a lot of things the developers did in this expansion. It's no wonder they lost almost have their subscribers.