It was said, that in WoD they will make DoTs scaling dynamically with your current stats. It's truly an issue, because it's hard to balance Damage dealer classes like Affliction Warlocks, and this is why Demo locks and Moonkin Droods (before they made the moonkin-trinket-nerf) performed too good in ToT.
I think it never was an issue before only in MoP. Why? They've just added too much procs/cd-s. Let's collect them (let's say you're caster), if you're a Tailor and/or Engineer you can have back/gloves proc, Meta gem: 30% haste, Jade Spirit 1650 Intellect, Potion: 4000 Intellect, Trinkets: 10k of a primary or secondary stat (UVLS 100% crit) and of course you can stack it with your 20-30% dmg CD and maybe 30% haste bloodlust.
This got a bit out of control in MoP i think, if DoTs can do 3 times the damage as normal in certain conditions it's no surprise DoT classes can become overpowered in some situations. I understand they added procs because "procs are cool", yes they're. But it becomes much less cooler if it will just sometimes effect will your mind blast hits 1k or 1.1k?, than effecting actual gameplay.
Personally i love it, when i can use some theory instead of just spamming my rotation/priority (It's mainly an Afllic lock thing, it's the only hardness in their game). And if i could choose between this with less procs, or when i just spam rotation i would choose the first. Players not deeply into DPS theories could still be able to do decent damage.
In my opinion 2 trinket procs/CDs plus a potion would do the trick, you can still stack it with personal CDs and Bloodlust, and your screen won't be full of WeakAuras proc progress bars (if you're a player like me) and DoTs will never be too overpowered. Enchants and legendary things should always be static, or a proc like legendary-back-kind-of-proc, which would be awesome for some trinkets too in the expansion.
Maybe not many people find this important, but if you do so, what do you guys think? Which system is the better?