I know you can't speak for the devs and can't be expected to be an encyclopedia of historical class nerf/tweaks/buffs/whatever, but that's why I'm trying to provide the best examples I can of how that would not be the case. Can you explain to me in more detail why you think that a Shaman would cast CH exclusivity with a baseline ranged increase when 25M raids do not do so now and the CH spread problems do not exist there? Is that based on your opinion or just what you remember Blizzard saying?
Think about Chain Heal for a second, then think about what Shamans bring. If you buffed it's range you would have a heal that:
-Increases your health size.
-Gives you a HoT (To be perfectly fair it's on a chance).
-Has a ridiculous range.
-And is a smart heal.
While it's not Healing Rain, buffing the range on CH would just make it stupid efficient to use a lot. The limitations of CH currently are technical and mechanical ones (as far as we know barring the glyph - I can ask GC though), but even they weren't there the developers still probably wouldn't increase the range any more than it is because it would be ridiculous.
I get that people feel like Shaman spread healing isn't where it needs to be at. And for all intents and purposes it's not - but buffing the range on CH isn't going to happen because there's already so much baked into the spell. You have your stacked heals, and then you have ones that are more flexible to be spread around the raid.
And out of all of those heals you want the one that's not only a smart heal but spammable to be your choice? Sorry, but I strongly believe that the developers would be against that.
Sensations suggested to change the RT Glyph to be tweaked a bit so you guys had a better answer to it.