I realize nobody runs Scarfswine, but it's on the site and was heavily advertised as a check (with Icicle Spear) to SubSD Garchomp. As nobody used Garchomp and everybody continued to spam Rain, SubSD Chomp wasn't an issue and Scarfswine never surfaced.
The calcs I ran used Superpower, so that explains that. Okay. He does a minimum of 97% with Focus Blast, but I've always ran Superpower. In my experience, the drop in power is made up in the perfect accuracy. I've won more games thanks to an opponent missing Focus Blast than I've lost because they landed it.