put a debuff or something on the target IF the spell is autocast which lasts maybe 10-15 seconds, so that the lightwell won't spam one person over and over.
This would be a choice the priest would make.
I know this has been suggested before, as I myself have suggested something similar years ago. But honestly, with blizzard attempting to make raids viable for pugs, it makes sense now.
If you only want your tank to get it, then turn off auto-cast.
as for PvP...well, it's the same deal with pve. It's always been there, but will simply make use of holy priest utility even if their buddy is..well...doesn't want to click the lightwell.
i sent this idea in as a suggestion ingame already. If anyone has a realistic counter argument, go ahead and share it...Or if you simply agree, then feel free to do so as well.
I'm not certain on the CD on the lightwell casting. with the amount of charges it has spread over 2 minutes, i'd say once every 7 seconds or something. (it's not exact, i know)