Ghost arc gets phazed out and relies on Focus Miss (while also doesn't always run special attack) so that's definitely a check. Tina-O doesn't run HP Fire anymore (rarely that is) and aren't even factoring Rain nor the possibiltiy that he doesn't use HP Fire on the switch-in so that's a another thing checked. A lot of Latias will opt for Psyshock (if even that) but yeah I should have specified it at least, still checks. Genesect don't often run Flamethrower nor max spatk and again no Rain so another thing checked. Ttar is slower than Skarm so he just Roost stalls for a miss and lols. If you have to opt for lesser/uncommon coverage moves than that means Skarm is doing his job.