The only cases against my argument is that the people who make the tiers cannot be bothered, and the foolish assumptions that it would lead to nerfing everything to make it usable in each tier under certain conditions.
Way to oversimplify everything. You're implying that those in charge of the tiering process are lazy slobs who do what they feel like, when the reality is much more complicated than that. As it stands, suspect rounds have been ongoing since the game came out in Japan way back in September to weed out most of the broken elements, and there's no telling how much longer it could take before we reach a stable metagame, what with the controversies surrounding permanent weather, Thundurus and Excadrill. What you're suggesting is that we should overhaul the
entire tier system; let's not even pretend that something this drastic would set us back
years before we finally get to that stable metagame.
The one factor you don't seem to be considering at all is that practically speaking, we also want a
lasting metagame, one that's not subject to wild variations, especially when it comes to figuring out which Pokémon is in which tier. The scope of the testing that your proposal requires basically demands that everyone keep up with
all of the tiering judgments of
all of the Pokémon affected by the process in order to continue playing competitively, which is most of them. And when that takes years, then that ends up being years that could have been played in a more stable and enjoyable metagame than the volatile one we have now.
I also want to point out that creating a separate tier for DW Pokémon is very much nerfing them: by definition, a nerf is when one arbitrarily prevents something from having access to an aspect they would normally and legally be allowed to have, which is what happens when we prevent a Pokémon from having a DW ability. It's not an assumption that your proposal would lead to mass nerfing either, because we're not saying that we
think that we will end up nerfing everything, we're saying that we
have to nerf everything. Doing otherwise would set a huge double standard in that we'd choose to nerf Blaziken by only allowing Blaze variants in the lower tiers, but not bothering to test out a nerfed (i.e., no Manaphy + Drizzle Politoed on the same team) version of Manaphy, for instance.
Once again, I ask: does having Blaze Blaziken (and I presume a number of other Pokémon, because otherwise, that would be blind favoritism on your end and you might as well admit that you just want to use Blaziken outside of Ubers and don't care at all about anything else...) in the lower tiers really contribute enough to the enjoyability of the metagame that testing your proposal would be worth the investment of dozens, if not hundreds of people's time? All I want at this point is a yes or no answer to the above, if only to get a sense of the motivations behind your proposal.