The platforming part feels fluid enough to be able to comfortably and accurately move forward. Other than the fact that every death resets you back to the very beginning, the difficultly actually feels reasonable despite the warning.
Just a couple of things: one, I'm afraid that audio was not cutting it for me. A 2-second loop that doesn't quite loop properly. In this instance, I'm afraid that silence would've just been better. And two, I don't think the "powerup" at the beginning was needed. Perhaps just state that you can double jump in the menu.