So after playing a ton and trying to find the best routes there are a few places that stick out as sore spots:

1-1, the pack of enemies with the helicopter. Attacking on the ground costs time, but I haven't found a reliable way to skip this pack. Damage boosting doesn't seem to be a time save here either.

3-2, obviously the water level when you enter the map highly dictates your route. Finding a way to force the water level or manipulate it somehow would be awesome.

Kitchen boss, should be beatable in 3 cycles as long as you get the pot to go to the opposite side wall first. I've put on the infinite lives code and fought this boss over 100 times but haven't figure out a way to force it. Not sure if it is just random or I'm missing something. Also the frame perfect bug used in TAS runs could move this down to a 3 cycle fight if you can get it reliably.

Attic boss, getting the piece that falls off to always "stick" in the boss when you throw it up is the biggest time saver. I've found that always walking to the right of the boss before throwing it seems to help, but not sure if there is an exact science to it yet.

I think its possible to get the sum of best segments below 15:00, and I would love to get my single segment run to 15:20.

Anyway, if anyone has any other thoughts feel free to post them.

Regarding the helicopters (and attacking on the ground in general), it's slightly faster to attack in the air. You could save a little time by attacking right after starting a jump, instead of attacking on the ground like I do.

Also a big time saver with the attic boss is that you can attack the boss directly with your sword after the arms fall off in the second phase. It's actually slightly slower to get the head to fully juggle on top of the boss, faster is to keep throwing it up, and getting double hits with it.

My sum of best is 15:15, no doubt 15:00 is possible.

Yeah I'm not sure if I could chain it well enough for that sequence. I'll give it a shot sometime though. Also for the Attic boss, I think in my 15:30 run I have submitted it never even got to the point where I could attack it with the sword, they died before they attacked in the final phase.

I think the biggest repeatable opportunity is figuring out how to get kitchen boss to always be a 3 cycle fight, I'm just not sure yet if you can always force the RNG in your favor.

I'm pretty sure the kitchen boss isn't RNG, the number of cycles the pot does in the background depends solely on exactly where the boss is when you attack the pot off. There is a decent spot very close to the right edge, and another if you stand just to the right of the tip of the spatula in the background (which is where I usually tried to go).

Getting the glitch on the kitchen boss would be even better, but I think it's basically frame perfect (and depending on where you are standing sometimes is actually a time waster).

AlaskanEmily had the idea to skip crowns to avoid the roulette, here is my idea for how to route it on Kevin 2 to skip up to 3 coins. The benefit for being able to skip 3 is crowns persist through death so you get a little bit of safety if you've messed up earlier.

After a bit of research, I've found a few interesting things out about the kitchen boss. To start, the boss' health is actually measured in chunks. After 5 hits, the boss will deflate and the boss is defeated on the 13th deflate. This means any number of hits that doesn't end in the boss deflating before getting back into the pot is a "waste".

This got me thinking what the maximum number of deflations you could get in 1 cycle. As it turns out, right at the beginning of the fight you can get 5 deflates in (instead of the normal 3-4) if you pull the boss all the way to the (radical) left. With this start you can actually defeat the boss in just 2 cycles! This saves about 10 seconds but seems to require a series of (near?) frame perfect strikes.

I did some more boss research, this time into the attic boss. Using cheat engine on mednafen I was able to find the boss' health and can officially say, after a certain amount of damage in the first phase (up top) the robot no longer takes damage. It starts with 16 hit points and after 5 (bringing it's total down to 11) it will pound the floor until it breaks through no longer taking any damage.

In the second half of the fight, the robot seems to not take damage when between phases. Most notably, it won't start taking damage after reassembling until it starts moving left/right despite visual and audio cues. After taking 5 more damage (bringing it's total down to 6) it moves into the penultimate phase where it's arms are spinning, 3 more damage and it's unto the final phase.

If you are inside the center of the robot (directly attacking) you seem to able to continue to do damage while it moves between phases to some extent (but not completely) e.g. from the circle phase to the spinning arms phase. I still don't fully understand why this is or how big the window is, but it allows you to beat it fast than you otherwise might.

Yeah, I kind of figured this (I thought I posted about it before?). You can jump into the boss in the first phase and get a ton of hits, but it doesn't speed up the fight at all. The last time I was grinding this out I figured out it's best to just get it down below as quickly as possible by having it jump on the same tiles over and over and not provoking any other attacks.

I think a few of the bosses have this property where each phase has a combination of damage and time/animations involved. I also suspect the Kitchen boss has a similar property with taking "damage" to knock if over, plus how many hits are allowed each time it's knocked down.

I finally got around to decompiling the part of the code the game uses to decided which way the pot will move during the kitchen boss fight. Unfortunately, the pot's movement direction is not dependent on any positional data but rather a pseudo-random value. During the boss fight the value only appears to change during certain player actions e.g. hitting the boss for the first time, spinning Peppers arm during an attack, pushing against a wall, etc. In theory, with enough amount of practice and control one could accurately plan/predict the pots motion but I think something like that is going to be TAS only.

One interesting related tidbit is the memory address of the pseudo random value gets reset to 0xDEADBEEF after the first gap jump in Kitchen 1. There are a few enemy events that cause the value to update, but it's possible to consistently play through Kitchen 1 and 2 without modifying the value further. Doing this I was able to consistently get the pot to go to the right after the first hit.

On the off chance anyone would like to look at code/value the relevant function for the pot movement starts at 0x00202460 in the Low Work Ram and the pseudo random value is stored at 0x06059968 in the High Work Ram.

Ah, that's unfortunate. Until this I had held out hope that there actually was no RNG in Clockwork Knight :(