This will be my last post on the subject to prevent derailing the topic even more but in response to the bolded part, you don't know that. You are theorizing it. I agree that sheer cold suicune set looks very threatening, but it has never been tested and who is to say that it would end up more threatening than regular crocune? Even if it was, why is it the default that it shouldn't be? If it was too good, then suicune itself could be banned without eliminating the strategy from every other, less potent threat that gets OHKO moves. The same could go for lapras (given that drizzle was still around). Is there some inherent reason that lapras/suicune shouldn't or couldn't be banned?
We are Pokemon players, not a team of fully trained scientists that require data to understand the simplest of concepts about the game we play. I can "theorize" Kyogre ripping up OU if we let it down and still be right. I can do the same for Zekrom, Reshiram, Mewtwo, and Palkia and I highly doubt a week of testing is going to suddenly say that they don't still hilariously overpower the rest of the game (that they were specifically designed to shit all over, mind you).
Even if you "require" proof before you believe that 30% is still too significant a chance to
automatically lose Pokemon, a lot of us don't, and the people in charge seem to agree. It's not for me to say whether or not this will be tested in the future, but my data is my experience in this game, which allows me to understand the significance of chance, luck, and what an unprecedented KO does to a player's strategy. I know Focus Blast misses like a bitch when I want it to hit and if I were sure that it'd KO a Pokemon every time it missed, I would put it on something bulky, spam it, and watch my opponent flail about.
And if you think stall is bad enough now with stuff like Rankurusu and the new, more powerful generation making it less viable, imagine what OHKO moves will do. On one hand, it will be viable because Stall members can switch to "hazards + OHKO moves", but on the other hand, having a single Pokemon just use Ressttalk shuffle + OHKO will shit all over it. It will be a very, very messy metagame, and even worse than the one we've had before or the one that is to come.
I'm seriously glad people like you aren't in charge because I don't want to have to go through two weeks of proving Mewtwo is broken just to satisfy your obsessive need for data on everything in the game. I'll take a more playable game over theories and science any day.