Obviously, and that's why they make recumbents and bikes like the Townie Electra, but none of those things applies to Catrin. She's on a road bike. If she takes both feet off the pedals, then both her feet are dangling in the air until she leans it to one side or the other. I suppose with a step-through frame it would be possible to hop off the saddle with both feet at once, but that would be very jarring to the knees, and certainly not an option for people with any of the physical problems you describe.