agreed for instance I'm pretty sure the AOE heal is supposed to be a standard action . since given a choice between healing one guy and healing everyone I doubt you would ever use the the single target...
Wait, are you talking about Curative Admixture? (The second Healing Infusion they get) If you are, I don't think I'm going to use that one very much at all. It gives a small amount of temporary hp for a healing surge spent on their part. I think the main problem I have with it is that it doesn't scale well, really.
At first, if you have a really good Con, you can break about even with a Wizard's healing surge value. It's still not as much value for a healing surge, but useful if multiple people need it. It quickly loses value, though. Assuming an 18 in Con, you get 5 temp hp until level 6, when you get 6. Even if you then max out Con with Demigod and stat boosts, at level 30, they spend a healing surge to gain 15 temporary hp. Doesn't seem nearly as useful as a single, extremely powerful healing that only spends one healing surge. At that level, you'd probably give the same amount of temporary hp to a group of 4 or 5 as would be regained from a single use of your other Healing Infusion.