A mastery that requires a hot to be cast twice in a target in order to get the bonus is a poor design if you ask me. They should have the bonus refresh on hot ticks rather than applying an entirely new spell. Especially with the mana cost of rejuv being so high.
Well thats good cause it doesn't work that way
New Resto druid mastery: Increases the potency of your heals on targets upon which you have a hot.
It benefits both hots and direct heals equally while still supporting Resto being a healer that cares a lot about hots. It encourages layering different spells while disincentivizing Rejuv blanketing.
1) You cast Regrowth on someone who has a Rejuv = bonus healing.
2) You cast Nourish on someone who has a Lifebloom = bonus healing.
3) You Swiftmend a Rejuv = bonus healing.
4) You cast a Rejuv on someone who does not have a Regrowth, LB or WG on them = no bonus healing.
5) You cast Rejuv on someone who has a Rejuv = no bonus healing. (You merely refreshed Rejuv.)
6) You cast a Wild Growth = bonus healing on those with preexisting hots.