Why does Deoxys-D even need an offensive presence? The fact that it already runs Superpower and Mirror Coat is enough to its most common "counters" in the tier. Xatu has been nonexistent in OU since the start of the Generation and that hasn't changed, so why is this relevant?
Deoxys-D needs offensive presence because it wouldn't have means of stopping many sweepers. Red Card is unreliable, and nobody uses Mirror Coat on this thing.
44 Atk Deoxys-D Superpower vs. 0 HP / 0 Def Mega Absol: 206-244 (76 - 90%) -- guaranteed 2HKO
Not really a free Swords Dance at all. The 44 EVs is what is being used to beat Bisharp with Superpower before it can kill you off with a Knock Off. So if Mega Absol has taken a little chip damage it can die to the Superpower. Not only that but Mega Absol is also nonexistent in OU, and few times I've seen it it was running 4 Atks because it's way to frail to try it to setup SDs.
But who the fuck even uses Superpower Deoxys-D??? Drain Punch is better as it doesn't screw up its defense. Even then, Drain Punch Deo-D kinda sucks. I'd also like to point out that even with Superpower, Deoxys-D needs prediction to get past M-Absol.
Which Rapid Spinners are being used in OU? The only one is Excadrill people and it gets 2HKOed by Superpower and can't always spin vs Deoxys-D. Here is an example:
Texas Cloverleaf vs Myself for the Sneak Tournament.
Excadrill, Starmie, Mega Blastoise and Forretress, to name a few.
Since when is Forretress relevant in OU? If it is running Toxic, it gives a free switch to Bisharp who can get a free Swords Dance, which you never want to happened.
Forretress can put the hurt on Bisharp with EQ (although rare) and Pain Split.
2HKO not OHKO. Deo-D still gets up SR in this scenario and then I can go to my appropriate Starmie check to prevent it from spinning. If this is the Mirror Coat variants then Starmie dies to Mirror Coat.
2HKO means Deoxys-D can only get up ONE layer of hazards per game. That's already a check.
You kind of have a point there but Pinsir is slower and gets Taunted. Zard X comes in on SR and it does Dragon Dance it's only getting 1 then it gets taken care of by Scarf Garchomp, Excadrill, or Landorus-T. Landorus will also get up one Calm Mind but Deo-D teams often carry Keldeo so Landorus isn't going to sweep there either.
Mega Pinsir just spams Return for the 2HKO and then switches to a spinner or a defogger.
It's bulk is beyond plenty for what it needs to do which is getting up SR and Spikes consistently. Stealth Rock + Spikes is enough for DeoD HO teams to be effective. The second layer of Spikes can be nice but it isn't needed in the slightest. Its Mono-Psychic has never stopped it from doing its job, not this gen and not last gen. Unless something drastic happens and Deo-D becomes less effective then we can drop it from S-rank, until its not happening.
Stealth Rock + Spikes, that is. Deo-D can't really set up more than one layer of hazards per game against a decent player, unless you either pair it with a Ghost-type or you are REALLY good at predicting.
PS: I honestly hope you weren't being serious about the mention of Drain Punch Deo-D when responding to Punchshroom...