As someone whose main is a cleric, I would prefer that this aug go to a Paladin. Yes, you read correctly. Since this affects only group heals, I don't need it. Why, you ask? Cleric group heals already kick butt. You can already crit for around 6K with your top level group heal. If your group needs more than that on a regular basis, 1) you're going to run out of mana fairly quickly, even with FT capped, and 2) you probably shouldn't be grouping in that area. If you're still not convinced, ask yourselves this clerics: do you *really* want an aug that's going to draw even more aggro since you'll be critting probably in the 8-9K range with your group heals?
A cleric with divine arbitration and a paladin who knows when to group heal are a group's best friends when a mob scores a lucky round.
Unless I knew all the paladins in my guild had this aug already, I would refrain from bidding on it. It is by *far* more useful to them than it is to me.