To reiterate one more time....
We're not going to let an attack that ignores armor do the same damage as an attack that is reduced by armor. The problem is that when armor gets reduced, a physical attack hits for more while a magical attack does not. The answer I keep reading is "Just buff Scourge Strike." No. It can't do more base damage as long as it bypasses armor.
Armor pen as a stat on gear is going away. The concept of reducing armor (through say Battle Stance or Sunder Armor) is not going away. It's entirely possible a spec or two might improve their armor pen through the Mastery feature. Even if it was going away, magical attacks still can't hit as hard as physical attacks. There would be no reason to have physical attacks.
At a very high level there are two options: Scourge Strike hits at X damage but respects armor, or Scourge Strike hits at X*0.5 and ignores armor. Talents etc. can modify this, but they all have their individual budgets too.
The sad reality of the current state of WoW simply does not support this logic. Warriors with 80% passive ArP, Rogues with wound poison procs nearly every hit and upwards of 7k envenom crits (not exaggerating to any extent), hunters with chimera shot/explosive shot, etc. The simple fact is all of these classes have attacks that ignore armor, or have a stat that they can gear that perfectly counters armor and has no downside to other abilities.
Anyways, just wanted to debunk the logic behind this nerf directly to prove that it was unwarranted and incompatible when compared to the current state of other "physical damage" classes.
And just for the record.. who was asking for a buff to Scourge Strike? (Read: last part of first quoted paragraph) The majority of DK's who actually knew what high level arena was like were asking for 1 thing: disease protection -or- some way to counter spam cleanse abuse in 3's and 5's. If that had been done DK's would have been well balanced. Not OP and not useless. Not a single DK worth his shit was asking for a SS overhaul, and especially not the abomination that is the new ss.