A Dance of Fire and Ice

This achievement (and, well, level) is very tough, especially when you're going in blind. It took me about an hour, but would probably take less if you knew what you were going into. So, true to form, i recorded a video of this level. If you listen hard enough you can hear my keystrokes but they're very quiet (sorry.)

https://www.youtube.com/watch?v=EI5_NohRSK4

There's definitely some advice i have when it comes to passing a level of this caliber, but first and foremost - and i know you're probably as tired of hearing this as i am - practice makes perfect. You're definitely gonna need some patience, you'll feel yourself learning the level as you try more and more, But anyway:

Use the in-game calibration. - I don't know exactly how much this helps but i'd imagine it would help sync things up if you don't have good equipment or are otherwise getting input lag. It's located on the far left side of the world select menu.
Use more than one button! - I can't stress the importance of this enough, i don't think it's humanly possible to beat this level with only one button. You need to alternate between buttons on the fast parts, like S-Bends and ESPECIALLY squares. I personally use Up Arrow and Z, but of course, any button should work with this game, so you should do what feels best.
Try using the keyboard instead of the mouse, or vice versa. - It's good to try different controls to see what works best for you. I used mouse up until maybe 6-X and noticed an immediate improvement upon switching to keyboard. Could very well hold true the other way around.
Try playing with a headphone ear out. - Meaning like, only put your left/right ear of your headset on, and put the other ear away from... your other ear. Try listening to your keyboard/mouse sounds. Try to time them up with the music. I have no idea if it helps, sometimes it works, sometimes it doesn't, but i'm only putting it here for the fact that i beat this with an ear out while listening to my keyboard.

Best of luck, this is still one of the hardest achievements i've gotten to date!