My understanding was that the evasion clause was only ever intended to apply to guaranteed methods of increasing evasion, not possible methods or even probable methods. While it may seem like it some days, Sandstorm is not a permanent fixture on the battlefield. You can counter it with your own weather or (theoretically) force your opponent into a situation where they cannot send out Tyranitar until after Garchomp is dealt with. Only when you cannot do anything at all to prevent someone from getting a guaranteed evasion boost should the evasion clause come into effect. If there was an ability that gave a passive +1 evasion boost with no strings attached, you better believe that it would be banned even if the only user was Magikarp-level. While the evasion clause most certainly could be expanded to include all evasion moves/abilities, just because it does not currently does not indicate some sort of inconsistency.
It seems to me that the argument to unban Blaze Blaziken boils down to "because we want to use him in OU/UU/whatever". Making concessions just to please a small subset of people undermines the whole process. Making people happy should not be our primary concern, we should be more focused on making the metagame as balanced as possible in the simplest, most elegant way possible. And creating a complex ban just for Blaziken pretty clearly works against that. I also think chickening out and going with a complex ban instead of just banning Swift Swim outright was one of the low points in my (admittedly very limited) time at Smogon, but that's a different discussion for a different time.
The only Pokemon I really see as really problematic right now is Garchomp. I keep hearing people say that Garchomp's simply not as good as he used to be, but that doesn't necessarily mean that he's acceptable for OU now. He's still faster than most non-scarfed targets, he still hits like a truck, he still has only a couple weaknesses (one of which is pretty rare), and he still has very solid defenses for a sweeper.
I could live with all that, but like with many other people Sand Veil is the tipping point for me, since it gives Garchomp a not insignificant chance of taking out a check without any real chance to do much of anything about it. It doesn't feel right when facing a Garchomp sometimes becomes a game of "how many Pokemon do I need to throw under a bus just to take Garchomp out". Admittedly, he's hardly the only Pokemon with whom you can end up playing that game, but with the others it's usually because of unlucky crits, misplays, or misses because of your attack's accuracy (while with Garchomp it can be any of those things on top of Sand Veil).
As for the earlier Ferrothorn discussion, I personally think he is acceptable at this point in time. If Ferro manages to get more than about two turns on you without being either chased off or killed, there's a fair chance you did something wrong. I mean, if he could run Stealth Rock, Spikes, Leech Seed, Thunder Wave, Gyro Ball, and Power Whip all at the same time he'd be over the top, but since he needs to choose his hazard and can only survive a very short while against anything with a decent Fighting or Fire move, I consider him more a major annoyance than something that's truly banworthy.
@jorm: Your doughnut analogy would lead me to think that you should simply get more boxes (tiers) rather than just cutting off and throwing away bits of doughnuts so you can stuff more into the box than it can legitimately hold (making the rules more convoluted than they already are).
