I was thinking about just carrying a a bunch of nourish and rejeuv glyphs with me into a raid. If I am tank healing, I'll throw on the nourish glyph and if I am raid healing I will use the rejeuv glyph (thinking particularly helpful for raid healing Hodir's frozen blows, Thorim's chain lightning and Mimiron Phase 2 and 4). Seems pretty simple, but i'm sure someone out there has thoughts and I'm particularly bored at work today.
if you dont mind burning through the mats, then it is a great thing to do.
necessary? no way.
Usefull? most definately.
I do the same thing for progression bosses. but once we get the hang of things then I usually just leave my nourish glyph in because none of my guildies have managed to learn that one yet and i'm tired of buying it off the AH.