I like how you can say Mistweaver was never a top tier spec in mop, yet guilds ran 2-3 mistweavers in t14, and 1-2 in ToT. The world second Lei Shen Kill had 2 mistweavers LOL. They made one of their holy paladins reroll from paladin to monk specifically for progression.
Btw Mistweaver was only "bad" in mop in the most unpopular raid size being 25 man SoO. In 10 man mistweaver was top tier the entire expansion.
I'm sorry your made up fantasy doesn't line up with reality.
I'm also quite confused, what exactly is the problem with being middle of the pack? I remember specifically in t17, Mistweaver going from the 3rd best healer to the 4th best healer depending on the encounter. Why exactly is this a bad place to be in for a spec? I mean, the spec brought a ton of useful things and did top tier hps. Seems fine to me lol.
Lets also talk about this "band-aid fix meme" because this is the most circlejerked thing in mistweaver communities. Yes, t18 4pc was extremely powerful. It was quite literally a 20-25% hps increase on most bosses. Same with the leech trinket. For non-absorb healers, the trinket was extremely overpowered. I remember the leech trinket being 35% hps increase on progression gorefiend at heroic ilvl. It's not an unfair comment to say Mistweaver got a lot of out the t18 power creep.
However people seem to stop here and claim mistweaver got this and it was required to match the hps of other specs at the time. This is an incredibly uneducated opinion to make on the state of t18 healing. To make this comment, you ignore the fact in that same patch, holy paladin got buffed significantly, and acquired the class trinket which was as powerful as extend life was to Mistweaver. Why did you never see people make comments saying "The holy paladin class trinket was a band-aid fix". Similarly, Resto Druid in t17 was in a worse state than Mistweaver coming to HFC, and also received the leech trinket, class trinket, demonic phylactary, and an extremely powerful t18 4pc. Again, no one makes such comments suggesting Resto Druid got band-aid fixed.
I want to make it extremely clear that I am not discrediting the idea that Mistweaver got a lot of out HFC power wise. I am stating that these continual comments about how Mistweaver was always bad and received band-aids ignores the reality of the game. The truth is if Holy Paladin didn't get buffed and receive the class trinket, they would have been as bad as Holy Priests in HFC. Resto Druids would have completely replaced their tank healing niche, and dominated their hps at the same time.
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I think the problem with Mistweaver isn't the developers being afraid to buff the spec. The problem is entirely the failure of a rework mistweaver got in 7.0. The developers were far too concerned with nerfing Fistweaving and balancing Mistweaver after being extremely overpowered at the start of the Beta they ended up nerf fixing long standing problems with the spec. It was too much work dealing with Fistweaving balance combined with balancing the initial state of mistweaver to fix the spec in time for live.
In future the developers should look at the Disc Priest rework in 7.2.5 for how you handle reworking a spec. Release the spec in a completely overpowered state, and slowly nerf overtime with raid testing in between nerfs to judge the strength of the spec.