Look, I'm not going to take sides on this, but let me make a few points to try and clear this up:

The purpose of Tidus' battle log was to prove that a Kyogre with max. possible Special Attack (in terms of level, IV's, EV's, nature and stat boosting) was capable of OHKOing a Blissey with max. HP and Special Defense (in terms of level, IV's, EV's and nature), in this case using Surf.

The question was not "Who would win, Kyogre or Blissey?", as that depends on many things; movesets, technique, stats and a bit of luck. It doesn't matter if you'd use different moves andyizcool, the trainer with the Kyogre could use different moves as well, not that that was the point of the excercise in the first place.

Ultimate Pikachu, in the line EVs: 252 HP / 6 SAtk / 252 SDef, the 252 SDef indicates that Blissey has the maximum effective Special Defense EV's, not none.