zorbees
Chwa for no reason!
Hmm, I think X-Act is also undervaluing the merit of multiple useful resistances. Of course you can get hit hard sometimes, but you can also take many other hits much more easily. I do think that his Blissey example was a little to extreme. Blissey does not take physical hits tremendously well as it has a low Defense stat and has no resistances other then the Ghost immunity. It isn't tremendously hard to wear Blissey down with repeated physical attacks. On the other hand, a Pokemon like Skarmory or Heatran can be tough to take down. Unless you're hitting extremely hard, you pretty much have to hit them neutral or better to take them down, which isn't that easy due to their Steel typing. Steel also helps offensive Pokemon switch in, whereas a Normal- or Dark-type may have trouble switching into neutral attacks if it isn't particularly bulky.
I'm also going to mention that STAB Pursuit doesn't matter that much. (I used a 299 Attack Stat and a Choice Band) The only things that STAB Pursuit KOs that nonSTAB Pursuit doesn't are Offensive Celebi (which Steel takes attacks better from), Roserade (which will either have a Sash or will have taken prior damage, meaning nonSTAB Pursuit could KO, also Steel is better defensively against Roserade), and defensive Rotom (which carries Will-o-Wisp and will Burn you and then stall you out with Rest). I suppose the higher the attack stat goes, defensive Celebi and defensive Rotom are handled a bit better by Dark Types, but I really don't think it is worth giving up the advantages of the Steel Typing. Offensive things like Salamence and offensive Zapdos are also handled a bit better but they don't use Secondary moves.
On Steel being a bad offensive type: That doesn't mean it can't be threatening. Metagross, Scizor, and Jirachi all use their STABs well. Dark isn't that threatening to things like Bronzong, Metagross, Hippowdon, Swampert, and Gliscor who will get up Stealth Rock either way, and most likely the fast pokemon like Azelf, Infernape (who threatens both Dark and Steel), and Aerodactyl will get up their Rocks as well. I suppose Dark works better against Dual Screen Azelf though...The Dark-weak Pokemon were covered in the section about Pursuit.
One last note, Dark would be a good Rapid Spinner due to the fact that it hits Ghosts hard with its STAB moves, but Rapid Spin cannot be guaranteed to be in the movepool. Also, we have evidence of a Steel-type Rapid Spinner performing decently well in Forretress, so it doesn't mean that Steel-types cannot Spin well.
EDIT: On the fact that many people seem to be assuming that the ability will stop/benefit from status: I don't see why this must be the case. There are plenty of other abilities that can work. I would rather see something like Vital Spirit or Insomnia, Early Bird, or even Poison Heal if it isn't a Steel- or Poison-type that can actually stop Sleep more effectively than a Guts SleepTalker, as IMO, Sleep is one of the most crippling statuses. The Trick preventing abilities are also there. There is Levitate to provide a Ground, Spikes, and Toxic Spikes immunity. Liquid Ooze, Natural Cure, Shed Skin, Shield Dust, Water Veil, and hell, even Soundproof are all other options. While all of these may not be optimal, I definitely wouldn't count on Guts.
I'm also going to mention that STAB Pursuit doesn't matter that much. (I used a 299 Attack Stat and a Choice Band) The only things that STAB Pursuit KOs that nonSTAB Pursuit doesn't are Offensive Celebi (which Steel takes attacks better from), Roserade (which will either have a Sash or will have taken prior damage, meaning nonSTAB Pursuit could KO, also Steel is better defensively against Roserade), and defensive Rotom (which carries Will-o-Wisp and will Burn you and then stall you out with Rest). I suppose the higher the attack stat goes, defensive Celebi and defensive Rotom are handled a bit better by Dark Types, but I really don't think it is worth giving up the advantages of the Steel Typing. Offensive things like Salamence and offensive Zapdos are also handled a bit better but they don't use Secondary moves.
On Steel being a bad offensive type: That doesn't mean it can't be threatening. Metagross, Scizor, and Jirachi all use their STABs well. Dark isn't that threatening to things like Bronzong, Metagross, Hippowdon, Swampert, and Gliscor who will get up Stealth Rock either way, and most likely the fast pokemon like Azelf, Infernape (who threatens both Dark and Steel), and Aerodactyl will get up their Rocks as well. I suppose Dark works better against Dual Screen Azelf though...The Dark-weak Pokemon were covered in the section about Pursuit.
One last note, Dark would be a good Rapid Spinner due to the fact that it hits Ghosts hard with its STAB moves, but Rapid Spin cannot be guaranteed to be in the movepool. Also, we have evidence of a Steel-type Rapid Spinner performing decently well in Forretress, so it doesn't mean that Steel-types cannot Spin well.
EDIT: On the fact that many people seem to be assuming that the ability will stop/benefit from status: I don't see why this must be the case. There are plenty of other abilities that can work. I would rather see something like Vital Spirit or Insomnia, Early Bird, or even Poison Heal if it isn't a Steel- or Poison-type that can actually stop Sleep more effectively than a Guts SleepTalker, as IMO, Sleep is one of the most crippling statuses. The Trick preventing abilities are also there. There is Levitate to provide a Ground, Spikes, and Toxic Spikes immunity. Liquid Ooze, Natural Cure, Shed Skin, Shield Dust, Water Veil, and hell, even Soundproof are all other options. While all of these may not be optimal, I definitely wouldn't count on Guts.