A nerf to Critical Mass was necessary. MoP should never hit Live with the .5 multiplier on CM, it was obvioulsy going to cause scaling issues down the road.
Let me try to explaing it in more details:
CM was added early in the MoP beta to address a couple issues:
- Make sure crit was the most valuable secondary stat for Fire. (Haste was just as good, and sometimes even better than crit throughout Cata)
- Provide the base crit for the spec to function and perform well at low lvl gear. (Fire lost more than 10% base crit from Cata to MoP with the changes to Raid Buffs, Prime Glyphs and Talents).
With the .5 multiplier, CM overdid the first goal, while didn’t manage to address the second issue well enough. It made Fire perform poorly in starter gear, greatly improve as ilvl goes up, and become OP at some point during the next tiers (maybe even by the end of this tier now that we can upgrade our gear with VPs).
Initially in the Beta, CM multiplier was .3. Then it was increased to .5. This should never have happened. Instead, some base crit should've been added.
The hotfix addressed the scaling issue. Unfortunately, we didn’t get the base crit we needed.
I strongly disagree that a CM nerf is the way to address scaling. The problem behind fire is not CM, it is the spell power multipliers on our 2 core spells: Pyro and Fireball at 220% and 150% respectively. If flat multipliers are a scaling issue, why hasn't Fury been touched? They have a 2x multiplier on their main attack. This multiplier is in effect for the exact same reason as CM - its there to smooth out the flow of the spec.
The "problem" we are seeing for right now is that Fire is able to obtain 32% crit (while forsaking all other stats) at around a 496 iLvl. What most people are missing though is that of that 32%, 5 comes from armor, 5 comes from Arcane Int, and about 7-8% comes from int. The remaining 14-15% is coming from gear. Basing the scaling off of Cata gear scaling (same scaling is used in MoP) we can see that you will gain approx. 170% the rating and int on gear going from T11 to T13h. That's basically from beginning of raiding to absolute end of expansion.
Keeping that in mind, you can estimate (fairly accurately) that fire mages will have the following available at "end of expansion":
5% from armor
5% from Arc Int
170% of 8% from int on gear for a total of 13.5%
170% of our rating from gear for a total of 25%
Adding those all up, 5 + 5 + 13.5 + 25 = 48.5% Figuring in the extra hit we'll have between now and the end of MoP, and you can probably bump that up to a flat 50%.
While that is "much" higher than our current 32%, you also must remember that gems and enchants don't scale. They are a larger proportion of your stats at the beginning of an expac than they are at the end.
So, looking forward to "end of expac", fire mages will gain in crit, but not anywhere near the 100% crit that people seem to assume we'll be hitting.
Interestingly enough, Spell Power also scales at about the 170% rate. So, that 25k spell power you have now, will be 42.5k at "end of expac". Knowing that Pyro gets 220% of spell power, and fireball gets 150%, can anyone else see the actual "problem" with scaling for fire mages?
Turn off recount. Take your favorite class and go beat on a target dummy. Is your class "fun" to play? Do you feel in control of your rotation? Do you feel like you are able to perform within the confines of your spec's intended design? This is setting all DPS aside - you're not even looking at the numbers. Just, how it feels.
The CM nerf made fire feel like you have less control of your rotation. It made it feel like we aren't able to play within the confines of the spec's design (fireball spam is not the intended design of fire). Because of these, fire is now "less fun".
Nerfing CM to fix some perceived future scaling issue is incredibly punitive to the vast majority of the player base. I am #674 for mages in the US (in terms of gear), yet I can tell the difference in how the spec plays post CM nerf. We are told "it gets better at higher levels of gear". Yet, there are only 673 mages with better gear than me in the entire US. With tens of thousands of mages raiding as fire every week, how can we say that it is acceptable for only the top 1% (or less) of fire mages (gear wise) to have a spec that is enjoyable to play - that flows and feels like a completed spec?
Also, I feel compelled to comment on this:
"Combustion needed a nerf"
Why? It is fire's *only* dps CD. The only one. It adds damage in the form of a dot. However, no other class has to jump through so many hoops to use their dps CD. It is also the only DPS CD that can have a wildly different impact on your "burst" based not only on your skill with the spec, but also luck, and also on your ability to use add-ons effectively.