While casters got some coefficient nerfs melee got some buffs directly (glancing) and indirectly (less cleaves etc) since the start of tbc. Removing the coefficient nerf for mages will put em quite a bit higher, 10% of 1200-1500dmg (not-buffed/buffed) times all the % modifiers is quite a big difference.. like popping 2 flasks.

The crafted tailoring sets were really strong, with the tailoring set + some random items you would be around 900-1000 +fire dmg for a mage. The only hard part was to get enough hit on the rest of your items.

Nowadays mages are around 1200-1300ish general spelldmg (can go a bit higher) but it's easier to cap hit. The gear we get now is more about getting int/sta/spir and not that much focused on extra dmg (compared to straight up +fire/arcane on spellfire). Tailoring didn't have much stats which resulted in the evoc whines, but at the same time were really efficient on the dmg stats.

For the tier pieces to come close to how good tailoring items were they have to make different +dmg sets, like a fire set for fire mages.. arcane for arcane. Other classes already can turn in pieces for different spec sets, so why not make it for the more basic classes as well. This will suck when you want to switch spec ofcourse, but it's the only way of upping the dps by a lot. Dropping random stats for dmg stats would help as well, but the tier sets always were the balanced items and you would just add random cloth to get extra dmg instead of stats.

Generally rogues win in dmg, but i don't mind. It's just that sometimes they seem so far ahead that i can't even dream of doing that much dmg even with the biggest crit streak. On another note, BM hunters seem to get ridiculously strong as well with the gear they get now. That is with a cat, not the cheesy scorpion.
Hope this isn't too much of a whine post, but some information about scaling

Waiting for the next itemization round is not really a solution, cause the same thing will happen again. Maybe blizz won't introduce new tailoring sets and all the casters will be behind from the start with no hope to get even or past the melee. If they want to fix it they can just look at how all the classes turn out now at the end-game and fix it.

Anyone else have any data? I think it was only a matter of time before it got nerfed.

...but it's still the best rogue trinket in the game, right? I mean it's kind of funny that they can nerf its uptime by almost 50% and nerf the effects of haste by 33% and it still comes out on top. Just shows how ridiculous the item was.

IMO it's more because there are a distinct lack of epic quality options in the trinket slots. If you think about it, what trinkets are available? Kara, theres romeo's vial (haha yay) then the only other epic quality trinket before Black temple (for all classes minus rogues) is tsunami and the threat one off vashj which is mediocre at best. So really, DST is still the best trinket for melee, not because its still actually great, but because there are no other options. Unless you feel it's right that you're still using heroic badge loot in BT than it is using Gruul loot in BT.