That wasn't my point, it you run Swords Dance, you almost have to run Sucker Punch / Iron head / Play Rough, if you run Fire Fang, you will probably not run Swords Dance on the same set, while Power up Punch takes care of that and lets you set up.
Or you can run Swords Dance / Sucker Punch / Play Rough / Fire Fang since Play Rough 2HKOs every relevant Fairy-type without a boost anyways, and most certainly will OHKO after a Swords Dance boost and Stealth Rock damage.
As for that set, it is sooo unusual, that it would almost surprise the opponent, making it really viable, I like it, hell, I'll give it a try, but know that is has no way to set up.
This isn't true at all.
I just told you that you outrun Trevenant, Gourgiest, and Jellicent with that set - 3 very relevant Ghost-Type Pokemon that will try and use Will-O-Wisp thinking they're faster than you. Pokemon like Tyranitar, Blissey, Sylveon, Florges, Clefable, Forretress, Ferrothorn, are all set up on or forced out. Pokemon that take significant damage from Sucker Punch - like Latios or Gengar - or are stuck on a Choice move you resist - like Genesect - are also forced out. Mawile has plenty of set-up opportunities because the opponent has to go to a counter immediately or risk +2 Mawile blowing holes through their team (and he won't know that you're not running the Swords Dance variant until after you've got your Substitute up).