essentially mirrors my stance on OHKO. We're talking about a competitive community that are composed of major control freaks - even 20% sand evasion is unacceptable, because "things get out of player's hands." Enter OHKO moves, which is far less situational than Sand Veil with a much more lethal side effect. At least you can change the weather and remove the effect of evasion from Sand Veil; there's absolutely nothing you can do to prevent OHKO moves from hitting you (OK, that's an exaggeration, b/c sturdy lol, Protect-stalling, and faster Sub users work sorta). Unless the mindset of Uber players are marginally different from the rest of Smogon players, I can't imagine OHKO moves ever getting unbanned. I'd love to test them out in the Suspect Ladder, and see for myself, though.
The most "competitive" unclausing would probably be Sleep Clause, because you can actually have control over what will be your sleep switch-in. Ironically, this is the one clause towards which most people have expressed strong opposition :o