Blue Dragon

[Zalvos]

I managed to get the beast deck together and I'm wondering if this trinket is great for Resto. The BiS post has it in the list, but does that mean this trinket is good all the way through Naxx or if it's just a good until I get something else.

[Doofoos]

This trinket progressing with your gear: more spirit you have - more profit you get.
Overall it does proc very well, im seeing blue dragon buff icon very often, but you shouldn't expect it to proc exactly when you need it, its random.
A week ago i get myself Zandalari trinket, and wanted to replace blue dragon with it, but after several tests i noticed that im running out of mana too often, so i switched back.

[Mirabai]

If I remember correctly that trinket doesn't proc off instant cast spells (not sure if this is blizzlike or not). Depending on how much you use rejuvenation this is something to take into consideration.

Also factor in the slow(er) cast time of druid healing compared to priest/pala, which means less procs than those classes.

With that being said, it might still be better than 2nd wind (which I'm assuming you're switching out for it).

[Doofoos]

If I remember correctly that trinket doesn't proc off instant cast spells (not sure if this is blizzlike or not). Depending on how much you use rejuvenation this is something to take into consideration.

It does (and it should), but on several conditions which i can't comprehend yet As example: im pretty sure it does proc from Moonfire casts without any restrictions, but for Rejuvenation proc conditions are very unclear. Looks like your target should have less than 100% hp on the moment of your Rejuvenation initial cast, or Blue Dragon wont proc at all

Also factor in the slow(er) cast time of druid healing compared to priest/pala, which means less procs than those classes.

Don't know about Paladins, but not every Priest is using Flash Heal spam And Druid cast times is not slower at all - it's 2 - 2.5 secs cast times for Swiftmend build, or 1.5 - 2.5 secs cast times for Nature's Grace build (and 1.3 - 2.5 secs if you are using Regrowth+Nature's Grace build)