I've made a freeware, co-op platformer a few years ago (back in 2015). Since I was already interested in speedrunning and played it a lot during playtest, I ended up learning and practicing running the game. The run can take from around 3.5 minutes (in the fastest route) to around 6 to 8 minutes (visiting every room and getting every collectible in the game).

I've considered submitting it here a few times, but I always feel like it's too much self-promotion, and I'm not too sure whether there's value in submitting runs that are already quite optimized (although I can still see some room for more optimizations).

What does the community think about a (hobbyist) game developer submitting their own game (and, then, their own run) to speedrun.com?

Generally speaking, there is no issue with a developer submitting their own game. Just because you happened to create the game doesn't disqualify you from doing and submitting speedruns. It is in a way self-promotion, but as long as it's apparent that you actually care about running the game, maintaining the leaderboard for it, etc, and aren't just doing it entirely for publicity, I don't think there's any problem there.

That being said, worth noting that there are plenty of reasons why a hobbyist indie production like this may not be added. From what I've seen, the site tends to reject a lot of lesser-known and/or lower-quality indie/mobile/web games due to the massive amount of those that exist (anything along the lines of "baby's first Unity game" or "I can't believe they let me put this on Steam #6845" gets virtually no consideration). Also, it sounds like your game is rather short (or at least the speedrun is, how long does a casual playthrough take?), which is another thing the site rejects games for, as noted in the game request rules here.

Out of curiosity, what's the game?

It's called JJAT, and it's available on itch.io (https://gfm.itch.io/jjat). The game's definitely short, but I was hoping that having a "all rooms and collectibles" category would make it long enough as to not be an issue, as it should be longer than 5 minutes. As for playthrough lengths, a blind race took 24 minutes (having most of the branching paths blocked out) and a friend of mine took at least 40 minutes to beat it (without any blocked path, but having seen the game before).

Out of the 5 points in the game request rules, it should be probably safe in at least 4 points (longer than 5 minutes; it is a functionally complete game; a speedrun can be quite optimized from a casual playthrough and it's not a fangame), however I do believe the game is quite unknown. Some of the features that allow you to go faster when doing an actual run are:

• One character may carry the other, moving at double the speed if being carried and moving in the same direction. Using this and the teleporter (an equip-able item) you may move slightly faster;
• Momentum is maintained between screens, so you may jump to start the next screen getting on top of the other character (possibly saving a few frames, although I never timed this);
• There's a wrong warp (using the teleporter while in hitstun from the last hit) that allows skipping one puzzle and a half;
• You may skip every collectible and go directly to the last area, but it becomes quite difficult/precise.

I'll consider this for a while longer, and see if anybody else has any other opinion on this. I'll probably try to request it during the weekend.

Thanks!

You can request it. I don't see why it should be a Problem that you made the game :)