Aka. Cloth simulations always simulate at 24 FPS, even if I have the project framerate set to 60 in my default .blend.
This means that if your project is on 60 FPS, cloth simulations will work at 2.5x speed. I’ve been searching for a fix all night, found some, but none that seem viable:
Keyframe scaling… You would get your character’s keyframes that you animated at 60 FPS, scale them by 2.5x and set the project to 24 FPS. Render, then speed up the final result by 2.5x.
Extremely fiddly, not a good solution when I’m going to require dozens of playblasts to get the cloth to look right. (project runs at 5 FPS, a’la BlenRig 
)
I also tried playing with the cloth properties(eg. Mass), Forces, but lower forces don’t give you the same result over a longer time - they just give you different results. Halving gravity helps with falling stuff, but springyness and everything else will still be twice as fast.
Tried enabling .pc2, exporting the cloth simulation into that format, then re-importing it using a Mesh Cache modifier. This allows for rescaling the time of the cloth simulation, but I realized this is not what I needed, unless I combine this idea with the next one.
I believe, although haven’t tested, that an equivalent to what I need exists for Rigid Body physics, which is a Speed slider under Properties>World>Rigid Body World. If anyone knows a literal equivalent to this for Cloth, please do share. Or any other viable alternative for using Cloth physics in a non-24FPS project. Also if I should be reporting this as a bug(which I believe it is) please point me in the right direction.
Thank you!