I think it might be possible to do the Sewer Spy stack sip in 1 player. You can do the spy stack using a crouch roll although it is quite tricky. Probably wouldn't be worth it but it would be interesting if it would be possible.

As for no detections/deathless runs, there are no current plans to add them. Exploiting falling off the map could be useful in like a 100% or Max% run where you go for the S+ ranks (although IDK how exactly to categorise 100% in this game current, all I know is that it's gonna be absolutely ludicrous).

Any idea how to get an S+ rank in the first place? I haven't been able to achieve that. The S ranks I got by deathless with loads, maybe deathless single segment? Do the pickups matter?

Yeah I just 100%'d the game after 41 hours (or 30 not counting erasing my save after the first 11), and some coins are bugged anyway so unless they get fixed there's no point counting them in hundo.

From what I’m aware of, you get S+ if you don’t get caught a single time.

All my 0 caughts 0 detections have been S ranks, but I did have to reload at least once in them. I'll try to do a single segment run and see if I can S+. I looked at the save file and there's nothing that suggests reloading hurts your rank, and the numbers that correspond to the ranks aren't linear (0 = C, 1 = B, 4 = A, 7 = S) which makes me wonder if they may be bit flags instead or something.

I figured out some consistent movement at the beginning of Downtown Panic which lets you get all the way to the car during the loading screen. This might only work in specific versions.

Nice, I've been trying to cook these but a lot of them seem to have pretty tight timings that I've had little success getting down. Best I've been able to do is roll but not change direction in time to start rolling before inputs get locked.

A way to skip the last vent section in prison + a way to get into the first vent early to skip two laser cycles.

A way has been found to stack loading zones. You need to hit further loading zones with your main character so while a double loading zone can be done in 1P, triple loading zone can only be done in 2/3P.

In Alex's last laser box puzzle, the lever is blocking one of the lasers allowing you to clip through the other laser and pull the lever. The game will progress even though you get respawned.