What I figured out after many frustrating deaths (other than that the collision detection is a liiiiittle off...) is that you basically need to hit jump and puke at the same time, rather than jumping and puking at the apex as I had been doing. You get WAY more height from your jumps if you hit jump+puke together, and you use way less puke as well.
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 "Retro Assault"){kind=icon}