During a lengthy discussion on the OI Discord last night, I think I finally understood what Game Freak was thinking when the Klink line was designed. I count it as one of my favourite evolution lines, even though it's kind of bad at everything. But it seems like Game Freak was trying to give it a niche, which is commendable, but the way this was executed is kind of painful, and the Klink line is far from the only example out there.
So, Klink and its evolutionary relatives are "blessed" with the regular abilities Plus and Minus. These abilities give a considerable Special Attack boost if used alongside other Pokémon with Plus or Minus in a Doubles or Triples battle. Famously, they were introduced to be the gimmick abilities of Plusle and Minun, but in later generations other Pokémon (and their respective evolutions) have got them as well: Dedenne, Klink, Mareep, and Electrike; the latter two have the abilities as a Hidden Ability only. You were originally required to have both Plus and Minus on the field to activate the boost, but from Gen V onwards, two Pokémon with Plus or two Pokémon with Minus will also get the boost. Essentially, the abilities are now identical, which makes it kind of sad that Klink got both of them - it was designed after they were made redundant.
Additionally, the Klink line was given the moves Magnetic Flux and Gear Up in the two generations following its introduction. These moves raise the two Defense or the two Attack stats of all allies on the field by one stage each, respectively - but it only works on Pokémon that carry the abilities Plus and Minus. Klinklang is the only Pokémon to learn both these moves, further working into its theme with Plus and Minus.
The fact that Plus and Minus boost Special Attack should explain why Klinklang has such a Special-oriented movepool despite having a Special Attack stat of a paltry 70, but 100 Attack it only learns three moves to use with. The Klink line is meant to use Plus and Minus to become Special attackers that also boost their Plus and Minus allies. And frankly, in that situation they're not bad; with a Plus/Minus boost under its belt, Klinklang has the same SpA stat as Magnezone, and all of the potential allies have an even higher base SpA. If you manage to get Plus/Minus to activate, Klinklang really isn't half bad, with powerful attacks and support moves at its disposal.
... but therein lies the problem. Because the niche clearly exists, but when the heck are you supposed to use it? Plus and Minus are the poster children of situationally useful mechanics. They only work in Doubles, for a start. In-game there are almost no Double battles, so there are extremely few opportunities to put the strategy to use even if you somehow choose to train two Pokémon with Plus and Minus and possibly keep moves that are useless in Singles. Heck, Magnetic Flux is an evolution move for Klinklang, and Gear Up is a Move Relearner move, so you won't get them until very late in your adventure. In conclusion, Plus and Minus are completely useless in-game.
That leaves VGC and the post-game battle facilities, where Plus/Minus is a risky strategy to say the least. Every single user of those abilities is either a Klink evolution or Electric-type, which means they're all weak to Ground. Also, they're kind of ass without Plus or Minus active, and the strategy requires the partners to be on the field at the same time - if one is KO'd, the other is dead weight. Klinklang's special movepool also mostly has Electric moves in it, which is redundant since all potential partners are Electric too. Plus/Minus is not a good strategy in higher-level play either.
So in conclusion, the annoying thing is that these Pokémon are designed around a strategy players will almost never get the opportunity to execute, which requires a convoluted setup and yields minimal payoff. Sure, Klinklang gets the same SpA stat as Magnezone if the ability is activated, but so does Magnezone itself, unconditionally, without spending its ability slot, and it gets STAB on its Electric moves to boot. And the Klink line is far from the only example here; there are tons of Pokémon with the same basic problem. They are centered around a strategy players will rarely get the opportunity to use even if they want to, and kind of useless otherwise. It suggests that whoever came up with the strategy stopped thinking after "eh, it can work" and didn't consider the necessary circumstances. Everything from the Pledge moves to Helping Hand to Follow Me to Mega Audino to Oranguru and Comfey's whole shticks. Decent in theory, horrible in practice because the use of those strategies isn't facilitated. Maybe they could work in a Colosseum-style game where every battle is Doubles, but then at least two of the necessary 'mons and the boosting moves would have to be made available early. As-is, the niches remain largely useless because the people who designed the Pokémon didn't talk to the people who wrote the encounter tables and nobody got the memo about how rare Doubles would be.
