1 frame saved on W1S3 by using dimension switch to bump earlier to get better vertical position
11 frames saved at W1 duo stage
36 frames saved on W4S2 by avoiding the bullet shooter better
5 frames saved at final stage by using a glitch to double jump/air jump... the trick is triggered by landing with satoshi on the moving platform which allows to jump with the clone too.
Saved 1 frame on W1 duo stage as stated in previous usermovie description. Probably final one.
(uploaded wrong file earlier)
edit: differences from the submitted movie:
11 frames saved at W1 duo stage
5 frames saved at final stage by using a glitch to double jump/air jump... the trick is triggered by landing with satoshi on the moving platform which allows to jump with the clone too.
edit2: new wip coming soon, 1 frame saved on W1S3 so far.
edit3: on new wip, 36 frames saved on W4S2 so far.
Duo stages can be improved using the "both walking right" trick, which seems to be the only duo trick that works in main stages. There might be a better route.
Edit: Apparently, most of the tricks actually only work in the last stage of extra world.
I didn't fully understand how wrong warp works, but I tried to send the right side Satoshi directly above after reaching antigravity, possibly ending the input much faster. Unfortunately, the moving platform didn't work.
Instead, I found another trick. In addition to only one Satoshi jumping, holding L+R makes both Satoshi walk right.
Also, an unuseful glitch: you can collect a pickup without making it disappear. It isn't demonstrated in this WIP; the snapshot below was taken from another attempt.
Some platforms are available in white "dimension" while the opposite ones in "black" dimension. There's a trick to fall through blocks from a spring but didn't save time in these levels.