From my learning experience, it's not that I didn't remember to unclip, rather sometimes / many times until you get the pedal cleat adjusted and broken in, sometimes it won't unclip exactly when you want, result a fallover.

Anyway rolling over may not be for everyone but, in my brief stint with cyclocross, my teach took me to a grass field and had me practice falling, rolling over. A better place might be a gym with heavy mats. It's a good thing to get used to.