I rode flats on my mountain bike in the winter (dry roads to snow and ice and with studded tires) and clipless on the commuting bike (touring DF) and mountain bike in the spring, summer, fall until one winter I realized that I was more comfortable with the clipless regardless of the conditions because they gave me better control and it had become absolutely no thought whatsoever when clipping out - as in I don't think about it, it just happens even if I come to a stop at a stop light and do a brake stand I'll then clip out if I need to put that foot down without thinking about it. When I went to the cruzbike it was flats but when I switched to clipless - ahhhh, welcome back - wonderful improvement. If you are ever at all awkward with clipless or tentative in your confidence in your abilities with them, then adding that to the new learning curve of Cruzbike just adds an extra facet that your attention can wander away from. But basically the same thing applies whenever you learn to ride with clipless - clip out earlier than you think you need to and you don't have any problems - we all break this rule and end up on the ground, thankfully that is not as far on a Cruzbike.
I do have an anecdote to share. I went for a functional abilities test for a job I was applying for. It worked out to being something like going to the gym for the first time and having a personal trainer push you pretty hard - pretty worn out muscles everywhere. I was wobbling all over the place drivers probably thought I was drunk at 4:30pm. Normally, I'm in complete control even if it looks slightly wobbly - I felt like I had no control because I couldn't use any backup strength to compensate because I had none.