As someone who couldn't care less about fighting games, I find the SSBM controller situation fascinating

Apparently some top players to spend thousands of dollars on controller mods to get a good controller and, before there were controller mods, maybe even more to find a good copy of a controller?

And there are all-digital controllers that fix the problems with "classic" controllers, commonly used in other fighting games, but they're considered unfair or even cheating by a lot of folks?

@danluu Historically, a portion of the skill involved in Melee was in finessing the analog inputs to do what you want, quickly and consistently. The “digital” controllers output exactly the right values on the analog axes to do the specific moves that people want to do in Melee. I don’t agree with the people who think it’s cheating or unfair, but you can kinda see where they’re coming from.
@cancel @danluu I mean, it's steps from "This controller will do specifically what I want to do even if tell it to do more", to essentially Turbo Controllers (Which admittedly probably would mess up your inputs, but importantly would *also* mess up your opponent's inputs in a pretty likely to be ruled "Cheating" way.), and then to TAS-input-assisted controllers.
@danluu oh boy if you think the controller situation of that game is a mess, wait till you hear about the rest of that game's situation
@danluu I love dropping in on a jargon-heavy niche subreddit and having to work out what everyone’s talking about from context. Like the first chapter of a @GreatDismal novel 😂

@danluu The rabbit hole on this actually goes pretty deep...

To do a dashback (high-level mechanic), you need to move your stick from neutral to fully left/right within a frame. This is very inconsistent because the game can poll for an input when the stick is ~halfway. So what you _actually_ want is a controller that occasionally drops inputs (a not-uncommon manufacturing defect, but luck of the draw unless you buy one at a premium), so the game sees the stick move to the edge instantly.

@danluu The ergonomics on the GameCube controller are also pretty bad. In fact, the *entire reason* that the SSBM digital controllers exist today is because one top player (Hax$) injured his hands so badly that he couldn't play the game anymore (let alone competitively), so then he went and built a new controller that he could use.

@danluu Non-official controllers (digital or otherwise) solve these problems and more. But of course, a good chunk of the community wants all non-official Nintendo controllers banned for the sake of purity or something.

...*except* to account for the inconsistency of dashbacks and similar mechanics, there's a mod that's common at tournaments (UCF). So why not just allow alternative controllers that give you the same benefits without the headache of modding the game?? 

@kylewlacy @danluu Interesting. Maybe one of my three GameCube controllers are worth thousands of $. 
@danluu Assuming it's fine to weigh in... the reason why the controller exists is mainly because of analog stick angles. Dashbacks and dropping through a platform while shielding are two maneuvers that can be much easier on certain controllers than others because of maximum analog stick values, and they're both very important.

It's why people mod their controllers, but also why you have the Universal Controller Fix mod for the game, which is a whole topic on its own as, despite being a godsend in theory, is banned in any tournament that may catch Nintendo's eye, because they get really pissy when people 'illegally' mod a game that's older than
me.

As of the all-digital controllers, they're not actually entirely tied to this issue ; originally, Hitbox, who makes leverless arcade sticks for traditional fighting games, started promoting the Smashbox as an option that was more ergonomic and consistent than normal GC pads. This earned it a ban pretty quickly, partly because the Smash community as a whole is culturally quick to call for bans.
Top player Hax, who suffered from a career-threatening hand injury, collaborated with them on improving the controller, but wasn't happy about where it was going, so he left to produce his own, called the B0XX. I'm pretty sure that one is legal in most places because he introduced limitations into the controller which appeased minds (also, probably because he had more credentials).

Hax later got banned from the scene for mocking a player for talking about being sexually abused by their mother and for being generally unhinged, but that's a story for another day
@danluu Nearly forgot ; here's a video by AsumSaus with great insight on controllers relating to Melee in general.
@danluu what the heck is that what happened here
Ahem... linking instead..
https://www.youtube.com/watch?v=Lw1tcqbFwN4
Banned Controllers for Melee (Legal Ones too)

YouTube
@danluu
All this controller mod nonsense could be solved in software, but every time someone tries to run a tournament with a mod that increases the dashback window from 1 60th of a second to 2 60ths of a second to eliminate the need for finding a controller broken in the exact right way, Nintendo sends lawyers in to shut them down.