I don't see how that's a problem. That's actually the point. Any change would lead to it not being OU as we know it. Unbanning Deoxys-S changes things. Even banning Moltres would change things (not much, but it would still be a change).
Then comes the question of too much change. Do we really want to rock the boat now?
There is no such thing as an objective way to measure this, and if you say so you are just fooling yourself. Give me any methodology and I'll explain its inherent subjectiveness.
Here's a better word: metric. We need a metric we all can agree on. I think everyone can agree that a metagame with more avaliable pokemon, more diverse strategies and room for innovation is a good thing. And while the
metric can be subjective ("Diversity" is good), the measurement or application of the metric can be completely objective... as long as the metric is good.
IE: We measure diversity with how many pokemon make up 5% of the game. But whatever it is, we need a metric, and from this metric we can make a completely objective test.
I don't presume to know what the effects will be. That's the entire point of testing.
My point is this: We need to know what to look for while we test the game. It looks like you also agree with me that a larger pool of pokemon is better? (if you do, thats a place to start for an objective test)
OU ought to have as many Pokemon allowed as possible. If you really wanted to have the largest number of viable Pokemon, you should have been speaking out against the tiers for quite some time now. Any diverse attacker, any fast attacker, or any attacker that can raise its Speed is worthy of banning. By allowing Garchomp, every team must have a Pokemon that resists Ground and Dragon (and your resistance to either probably shouldn't be weak to the other, or you are in trouble with Swords Dancers... too bad only 2 Pokemon fit the bill for that double resist!). If Infernape weren't kicking around, I wouldn't need to have Tentacruel, Slowking, or Dugtrio on most every team or risk annihilation. Gyarados means Starmie, Celebi, or HP Electric Waters need to be there.
Irrelevant. The only case for banning pokemon is "does it improve the metagame?". Subjective, yes, but I feel we should break it down into metrics and from there measure the changes to the metagames.
I also know you can make a good team without explicit counters. My original hail team which reached #1 on Shoddybattle ladder had a major Gyarados weakness and no counter to Garchomp. That didn't stop my team from reaching the top. Admittingly, Garchomp had a problem with blizzard on every one of my pokemon... but Gyarados was still a major problem.
Further, with solid metrics, we will be able to argue theorymon at a much higher level and certainly make more progress.
But by doing that, you are testing the Pokemon in an environment which may not necessarily mimic how it actually ends up. Then, when you eliminate one Pokemon in the first round of testing, it will be almost impossible to overcome the inertia to retest it once you find that four others are OK. When a Pokemon is truly broken, it forces you to change. Unbroken Pokemon force nothing.
I find this interesting. Back on the metric topic, where do you rate change in the metagame? Certainly, how much a metagame changes as a result of releasing a pokemon can be somewhat objective (Deoxys-Speed did like... nothing. When Manaphy was banned, Ludicolo and Raikou certainly became much less popular).
From your last sentence, I'd assume that big change in a metagame is a bad thing. Certainly, adding 2+ pokemon into a metagame will force a change much more than just adding 1 pokemon, especially when these pokemon are clearly very powerful.
Finally, I somewhat challenge that point about inertia. I agree that there is inertia that keeps Manaphy and Wobbuffet Uber (from their early tests were in Smogon tournaments and Smogon OU). Between then and now, the only change to the metagame is that Deoxys-Speed is OU (on the Shoddy-ladder at least). There is inertia behind Manaphy because the metagame technically
hasn't changed since the last tests, and Deoxys-Speed is really irrelevant as far as countering Manaphy is concerned anyway.
Every Pokemon are "niche" Pokemon. For Pokemon like Garchomp, their niche (overpowering attacker that KOs stuff that resists it) is a pretty large and useful niche. For others, like Quagsire, that niche is currently pretty small. I find it highly likely that Kyogre alone would be a decentralizing force, not an overcentralizing one. If nothing else, it lets you counter Garchomp a lot easier.
Will some unpopular pokemon become more popular? I don't doubt it. Bologo made a case with Seaking, Ludicolo and other water pokemon who benefit greatly from Rain. But we will lose out on at
least the UU / BL fire types with Rain killing their attacks.
Kyogre will centralize the game around water and away from fire pokemon. Just because a few pokemon benefit does not make it "decentralizing". You'd have to include the pokemon that are less popular / no longer usable when these pokemon come in.
That's precisely my point! The only truly valid test would be to make this the standard (as in ladder on Shoddy). In fact, any other test is far more plagued by bias. If we rely on subjective reports from tournament participants, it's going to be biased toward the Pokemon being uber. If you play a game and the Pokemon either doesn't show up or doesn't do anything special, then that's nothing to report. Could you imagine someone making a thread "I didn't fight Azelf my last battle!" or "Gengar seems to fit in OU"? That's not noteworthy. If you lose to Deoxys-S and therefore think it's broken, you are far more likely to report this datum.
There is a primary problem. What if people don't want to play with Mew, Manaphy, and Lati@s?
The Shoddybattle ladder would indeed be the best test, I don't doubt that, but the primary purpose of the game is
fun. Forcing hundreds of players to beta-test a major change to the metagame on the Shoddybattle Ladder is unfair to the players. Testing of big changes ought to be done by people who are willing to test the metagame, not by forcing everyone to a certain set of rules all at once.
