For one thing, just because something has counters in OU doesn't mean that it's not an Uber. Skarmory is countered by Probopass so therefore Skarmory must be UU. Of course not. When you look at the suggested movesets for Deoxys-E, you don't realize they're tailored specifically for the Uber environment alone. Those movesets obviously don't hold up as well as they could in OU. Deoxys-E could easily have a destructive OU moveset with Hidden Power [Fire]//Superpower//Shadow Ball//Psycho Boost/Grass Knot. That just removed every counter you listed with room to spare. You could even put Recover on it, since its defenses are decent (sans the HP) and it'll be able to snag a recover in before any non-priority attack or Ninjask (after 1 speed boost).
Blissey doesn't exactly shatter the metagame the way you seem to think it does. There are things in this world called "physical attackers" that kill Blissey no problem. But for Deoxys-E, you'd need priority moves on at least 2 Pokemon or you'd need a Substitute/Protect/X-Scissor Ninjask (which may not OHKO, I'll calc that). 476 SpA is a lot and very few things can withstand it (that's Choice Specs, LO is 412). It's not simple enough that an Aldaron Hitmontop will OHKO it no problem with Bullet Punch (like Deoxys-A...by your logic then, that would make Deoxys-A an OU).
Additionally, people who think only Kyogre and Rayquaza and Palkia should be in Ubers (people who post these topics) simply prove they know nothing about Ubers.
No.
The moveset you posted is retarded because it has 5 moveslots, and just because it hits something SE doesn't mean that thing can't still counter it. HP Fire doesn't change anything(excpet for Forretress). Even if you could manage to get HP Fire 70, it wouldn't come close to OHKO'ing Bronzong, Jirachi, or Metagross while all those pokes can hit it's weak point for massive damage. Bronzong with STAB Gyro Ball, Jirachi with U-Turn, and Metagross with CB Bullet Punch or Pursuit.
The problem with Choice Specs is that it gets easily beaten by prediction
If Deoxys-e was allowed in OU, and you were getting a battle where Deoxys could possibly be on your opponents team, how much would you have to change your current team to be prepared for it?
I wouldn't have to change mine at all.






