So, I was going to stay out of this, but I must speak up and say something...
To all you Pro-lightspring people, the main argument I see here is "People didn't click it, so it was wasted, this is a good glyph". So, why didn't YOU click it then? Even if no one clicks it besides yourself, you can easily use all 10[5] charges in 3 minutes. I know this because I am the only one who used the Lightwell on our H Zon'ozz kill because I told people to not worry about the well and focus on DPS. Think about it, you get the same effective healing, as long as you arn't using it while at full HP ofc. If even just you click the well, that saves mana you would have spent on Binding Heals likely, or other heals from other players. Sure, its not ideal, but you still get some damn good use out of it.
There may be one or two places this could be useful, but only if all the charges can be expelled at once. If it has an ICD, then this is useless. If it doesn't, could be useful for predectible AoE Spikes, i.e Madness Bolt hitting, 4 seconds before it hits, put it down, explodes, heal scan triggers, everyone get a HoT. It might be good then, cause DPS is prob trying to burst down bolt as fast as possible and may be inclined not to click the well, but any good guild would click it right as the explosion, so w/e.
I just don't see why any Priest should want this. If you think people are not clicking it, then maybe the same can be said for yourself... At least this glyph will do one thing, it'll let me spot a bad priest a mile away... I don't want to be that mean person, but seriously, I have NO trouble using all 15 charges of my Lightwell if I have to, maybe before you soley blame your LFG/LFD/Guild on bad clicking, you should look in the mirror and ask yourself, "Do I click my Lightwell?"