Dashless 1A isn't as hard as you think - just go into options and remap the dash button and then take it one room at a time - you can die as much as you want, you just aren't allowed to dash. Watch a video if you get stuck. I was able to do it in one sitting.
I got it the other day after finishing 5B! I got curious about skipping the keys in 5B, which involved a lot of spike jump tricks (ended up not doing them), and then polished off 1A dashless the same day. I definitely followed along with a video, and I had to restart after a few of the hard rooms after I instinctively dashed to save myself.
I don't think I thought it would be hard, I just wasn't interested in learning precise spike tricks when I started going for golden berries. It was more interesting to see how the easy levels play out when you have to memorize and execute the whole thing at once.
