Let's use a less borderline Pokemon, then:
The OU metagame works just fine without Rayquaza, and thus doesn't need him.
The inverse of that is not that OU only needs 6 Pokemon and the rest should be removed. I don't know how to make this point clearer.
I never implied that "OU only needs 6 Pokemon" or thought that was what you were trying to imply. I'm willing to temporarily accept that Blissey is "necessary" to the metagame for the sake of your argument. However, you're again using a flawed premise in "The OU metagame works fine without X pokemon, and thus doesn't need [it]". This is not how we determine what is uber and what is not. The standard metagame did not "need" Deoxys-S—we are testing it because it perhaps will not overcentralize the metagame as much as we once thought it may/assumed it did.
Regardless, at once you begin to see that "works just fine" is kind of shaky in and of itself. The Garchomp issue is perhaps indication enough that our metagame isn't perfect and perhaps needs a pokemon that counters it without overcentralizing the metagame (maybe this is Deoxys-S coincidentally, maybe it isn't) or that Garchomp itself overcentralizes the metagame. It isn't the case, though, that Garchomp is or is not necessary to the metagame—that doesn't enter into the equation at all. It doesn't for Blissey, either, since it by itself does not overcentralize the metagame. It's just a coincidence that it happens to check myriad special threats by itself and therefore prove itself somewhat "necessary". But this isn't how we determine what belongs in standard and what doesn't (nor do we cite the fact that a pokemon checks a lot of pokemon by itself and therefore may be uber, which is what brought this discussion up in the first place).
I know exactly what you're saying, but I wholeheartedly disagree. I'm not (and never have been) suggesting we should be taking opinions from idiots. By looking at the Shoddy stats I can see a hell of a lot of people who aren't using him, and I very much doubt there's nobody in that group who has a knowledgeable opinion. We don't have to look at the group as a whole and say "Well almost everybody hates him", it can be narrowed down to people who actually know what they're talking about. People are avoiding Wobbuffet, no doubt, and I think it is short-sighted to liken every single one these people to those too ignorant to see why Blissey is important.
I'm not likening the people themselves from the Wobby issue to the Blissey one, I'm likening the arguments. There's a big difference there. I've said a couple times now that it is a bad idea to only take the mass opinion on a pokemon into consideration when deciding what to do with it. A lot of people literally have called both pokemon "gay" and "cheap", and a similar number have said things like "blissey dies to any physical hit i dont see what the big deal is??" and "u-turn and baton pass counter wobbuffet pretty easily". These "arguments" are horrible, and the better ones need qualification in the form of battle logs or a least lot more words that clearly indicate the battler knows what he or she is talking about if they're going to hold any water.
Seriously? So if we were talking about Garchomp and I said "Garchomp can kill most OU Pokemon it faces before it gets killed itself", you would turn around and say "Not Weavile! Not Mamoswine! Stop making it out to be something invincible, lol show me the logs where it kills 6 things completely unaided, rant rant rant"? Because that's exactly what you're doing here, and its completely stupid.
DISCLAIMER: From this point forth, when referencing Wobbuffet's capabilities, I am only talking about Wobbuffets who haven't already been completely crippled.
And that's all I'm going to say about that.
Don't call any of my arguments stupid, that's unnecessary and bordering on staff disrespect. And besides, here you say "most OU Pokemon", where before you added no such qualifying number or condition. You're probably just not going to admit it, but saying "you either die or let it turn you into set-up bait" is an unyielding, black and white argument, and it was wrong. You are now qualifying it as it should have been, but don't pretend that you weren't exaggerating when you gave that either/or statement, and definitely don't start taking shots at my intelligence when I call you on such a blatant exaggeration.
Anyway, I don't really care about the "weakened" Wobby arguments, because that's entering the realm of theorymon to which we shouldn't waste time attempting to do justice. Actual competitive play by itself proves enough that there are many, many scenarios both where Wobbuffet isn't as invincible as some people would have others believe on paper and that it's more cheap that "u-turn and bp are counters" arguments would would otherwise dispel.
Again, I'm not insinuating that a Garchomp test would give us any new information on over-centralization (or to what extent Garchomp does it), and in fact it might not turn up anything of interest. But the thing is, its a simple and easily workable test that might give us something interesting (10 more Pokemon might become usable for unforseen reasons, who knows?), but even if it doesn't there's really no harm done. At the very least, it would most likely do away with the "If we ban Garchomp, then something else will just take its place and we'll want to ban that!" argument, which is still a small step forward on the whole Garchomp issue.
Of course, again, all my comparison between the two tests was meant to show was that an almost harmless test probably isn't going to be done while a test that could have knocked the metagame around completely went ahead with no public (as in, on the forums) discussion until the day before it happened. I'm not saying either test is more worthy than the other.
I dislike the "if we ban Garchomp, then something else will just take its place and we'll want to ban that!" argument as much as you do, which is something else we can agree on at least to do away with that being a good reason to test Garchomp. We still need a better reason though, and this is probably not the place to discuss that.
And I'll remind you that these aren't the Shoddy Battle forums. Wobby was unbanned on Shoddy battle, and Colin was under no obligation to run that by all of us on Smogon before doing that. Now, he is one of our most respected Policy Reviewers, and is running a lot of things by our competitive battling community, but the Wobby unbanishment happened before he was very active on the forums.
No, I don't have a better alternative. Right now there is no better alternative, although I don't think it would be so hard to create one: For instance an invite-only Shoddy server (and only inviting decent/level headed battlers) could be better if a large enough sample crowd was collected. All I'm alluding to here is that if Smogon/Shoddy's core userbase is so horribly aligned to the anti-Wobbuffet side (which again is something I'm drawing from the stats), then I don't see how efficiently any tests can be done here.
I can't help but initially think of your stance on how easily a Garchomp test would be initiated while at the same time thinking that a Wobbuffet test is that much more invasive and unfair to the community.