Don't make a post just to quote mmo-champion or a blue post; add something original of your own to the conversation. If you don't have anything worthwhile to add, then don't post.
From Patch Notes
Tier 12 Bonus and Chain Heal
Chain Heal’s bounce range has already been increased about as much as the engine supports without causing odd behavior and/or undermining the purpose of the spell. It’d certainly be a better spell if it jumped 20 yards, but at that point it’s just a smart heal with a funny visual. And if it can bounce to the same player multiple times, then it’s just the best heal to use, always.
I think you're undervaluing the benefit of not consuming Riptide. That potentially amounts to a sustained 25% boost to Chain Heal’s throughput, which is huge, in addition to the healing conserved by not losing a portion of your Riptide. And while Chain Heal is easier to use efficiently in a 25-player raid, if the heal hits three targets it is quite efficient, and those situations will arise frequently in 10-player raids.
Ultimately, because healing gameplay is naturally varied (as opposed to DPS rotations for a min/max player), whenever we come up with healer set bonuses, unless they’re incredibly vanilla, they will inevitably favor some healers’ playstyles over others. And the latter group will say “but I never use , this bonus is terrible!” while a separate but less vocal group is giddy over what they’re getting. The original bonus was flawed because it really did play directly into the greatest weakness of Chain Heal in 10-player raids by requiring a 5th target to be of any use, but this bonus will be incredibly strong on 10-player Firelands encounters like Fandral, Beth’tilac, Rhyolith, and more. And on the encounters where it’s weak, Chain Heal isn’t really the right spell to use in 25-player modes anyway.