That wasn't directed toward you, it was directed toward the "defog invalidates spikes klefki"
And obviously we're not talking about throwing klefki at any point to spam twave. Also the team does NOT need to be full of frail sweepers for swagkey to do some serious damage. Once you get a sub up with parafusion, they're pretty much dead.
And again, i never denied that there might be better roles for klefki, just that the arguments against the paraswag version were faulty because they presumed it was way less reliable than it was. The fact is, dual screens/spikes will not always be a relevant strategy because they can just switch in a set-up/stall, which paraswag klefki counters.
These two arguments are already faulty, easily the biggest team archetype SwagKey has trouble with is stall, as they have high defenses, low offenses, and healing moves. They can afford to switch around and stall out Klefki, while Klefki has to repeat the whole Swagger process just to be able to get reasonable damage off (as a former SwagPard user, who has STAB on said move, I can relate to how difficult breaking defensive teams with SwagPard can be). If the wall is suffering confusion and paralysis, they can switch back out to avoid a strong Foul Play. If Klefki does not Swagger on the switch-in, the switch-in can try to pull off at least one attack on Klefki to break its Sub. If Klefki does get the Sub, hurrah for you, enjoy the strenuous task of killing 4-6 bulky dudes with this (if anyone of them has Regenerator, Klefki would be the one suffering through hell, not the opponent); if you don't get the Sub immediately, that means losing more HP to keep one up, and while Klefki's defenses aren't terrible, even stall will have an easier time taking down a weakened Klefki. Gliscor and Hippowdon are two such examples that SwagKey will have a hell of a time trying to break through and basically offers a free switch into; SupportKey can lay down Spikes then gtfo, mission accomplished.
So as i stated already, Klefki has several valid ways to play, and trying to say any of them are overall better than the other because of a fallacy such as "reliance on luck" (when pokemon is already largely reliant on luck) is invalid.
Indeed, Pokemon is reliant on luck, however to focus solely on this luck as the main strategy of the Pokemon can either go off without a hitch or court disaster. Almost all Pokemon try to function with some sort of consistency so as to avoid being deadweight. You don't see a Pokemon run Inferno or Zap Cannon to status foes, you see it use Will-O-Wisp or Thunder Wave (assuming the Pokemon learns both attacks of their respective elemental type) because trading the better reward for guaranteed consistency is generally better than going for the greater reward with a risk of doing little / nothing. While Klefki's typing and not-paper-thin defenses do help to lower the risk, it lack of consistency compared to support sets generally make it a tad inferior as a result: No one wants to see their Klefki get wrecked by a stray Earthquake or something like an Infiltrator Noivern's / Chandelure's Flamethrower from sheer chance.
The fact is, swagkey is very consistent on anything that cannot 2hko it or worse. Throw it in against ANYTHING that can't 2hko it, and you have a very good chance to set up and wreak havoc(note: sub essentially makes all future pokes 2hkos and gives a 60% to lose their turn, if they can be paralysed). Consistency is very important, and while yes, it can backfire, so can focus blast and any not 100 acc attack(Even those but not reasonably)
The chance of getting a free turn on a 2hkoing enemy is 62.5%, assuming you can twave. This is cutting it pretty close, but let's look at 3hkos or greater. Which is 81%, which is about the same as stone edge.
Now let's remember that if that succeeds, you're also set to severely cripple or even knock out a second pokemon, because you're likely to have a substitute set up. So, assuming they can't 2hko you, you have a very high chance to take out their pokemon, and cripple/take out yet another.
I'm trying to look at the odds here. If the opponent has a Ground- or Electric-type, these odds can fall significantly. Thunder Wave has a 25% chance of immobilizing an opponent, whereas Swagger has a 45% (counting miss) chance. Let's say Klefki switches in on a helpless Pokemon. You get Sub up, they switch to Electric- / Ground-type. You Swagger, they have a 50% chance to fail to break the Sub (let's say they don't). You prepare to Foul Play (because there's nothing else you can really do), they now have a 50% chance of breaking your Sub (the odds of failing / hitting twice in a row is also ~25%, so it stands to reasoning), which they do and then eat a Foul Play to the face. Now what? You can't Thunder Wave them, you can't Swagger them again as they can very well snap out of confusion right about now (this is totally random, you don't know when this will happen), and for physical attackers, you've just given them a +2 boost. This is the kind of risk I'm talking about: by playing solely through luck, you have no control of the situation and hope Lady Luck doesn't backhand you in the face....and this set somehow isn't inferior to the more consistent SupportKey sets?
Let's also remember the following:
With leftovers, only 3hkos which do more than 41% will leave klefki unable to make a sub after two successful hits.
If klefki DOES fail even an attempt on a 2hko pokemon, you're next pokemon is likely able to set up on the next pokemon. So unlike stone edge misses, it isn't a total loss.
This klefki can still be supported, you insist on it being a one-man show but the fact is it actually can be synergetic with other pokemon. Skarmory for it's physical walling/earthquake avoiding needs for example, and flash fire or even assault vest tyranitar for it's fire/special needs.
If klefki switches on a non-attacker or something without the tools to do good damage too it (with steel/fairy, highly likely) then it can get pretty much do w.e it wants. Set-up steel types like skarm/ferro/forr/etc are good examples. They just cannot do anything. (though with ferro you sub first)
This klefki is essentially to punish the opponent for sending something out that can't kill it.
Other Klefkis cannot do this? Personally I'm more worried about Spikes all under my feet and / or Dual Screens that halt my sweepers as well as the possibility of a whole host of setup sweepers rushing in with their newfound protection than some silly parafusion set that may or may not end up dying / killing itself. Other Klefkis commonly carry Thunder Wave anyway, so SwagKey's merit of occasionally stopping rampaging sweepers is rendered moot.
That said, if you already have wallbreakers or other anti-set up mons, or just in general need support, obviously dual screens klefki is for you. However, the concept that SwagKey is inconsistent seems faulty with the actual data. And personally, and i mean no offense by this, I feel like there's a personal bias against the strategy, rather than purely objective criticism.
There is indeed some bias against Swagger as you said (and have seen), but as a parafusion Liepard user myself I can relate to the shortcomings to the set. Sure, it can sweep teams from time to time while totally wasting the opponent's Musharna and stuff (or just drop dead :P), but even Liepard has better things to be doing. Klefki here has the tools to help teammates sweep: SwagKey can stop a rampaging sweeper and possibly kill it, but SupportKey can not only stop said sweeper, but also set up either Spikes and / or Screens so that his teammates can carry on the sweep for it (this is also directed toward the "one-man-show" thing I commented about SwagKey earlier).
Essentially, it's a MORE consistent paraflinch (it's parafusion) mon that can be switched in against many pokemon, and can gain way more momentum despite togekiss losing it after it's first kill.
At this point, I may just have to take back what I said about agreeing with Klefki being the objectively better SwagPlay user; Liepard still has merits, namely its speed (outspeeds Excadrill, Rotom-W and Garchomp), Steels not resisting STAB Foul Play (at least Fairies do not have titanic physical bulk) and Encore, which can guarantee the free turn of setup, unlike Thunder Wave. Sure, sound-based moves weren't favorable for Liepard and its bulk is pretty shit, but even SwagPard can boast more consistency than SwagKey, since STAB Foul Play hits defensive teams a tad harder and Encore can screw up their attempts at healing, nabbing yet another free Sub.