As far as I know, gemskip means beating the beginning without touching the gem. When you do that, you have 1 dash, but the game is still possible.
some of these levels are a pain, but all of them are possible. You can find a walkthrough on youtube if you can't figure out how to beat a level. I've beaten this game on the normal difficulty in 9 minutes 42 seconds with all berries and I still couldn't beat the game with gemskip, so don't worry if you're stuck too.