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This is a very good thread, a good read actually, and worth reviving. I spent a lot of time in my trainer when I first went clipless as I was determined to get out of toe-clips. This was in the late '80s, when I bought the original Look pedals. It took a while but I got the hang of how it worked before hitting the road. I then tried Keywin Pedals, and had my only clipless fall as they were very hard to clip out of. Too bad, as they weighed half what those old Looks weighed, but they took a feat of strength to twist out. I then went through early Shimano Dura-Ace look style, and Time before settling on Speedplay over 10 years ago. I found Time for my MTB and never looked back.

When I need to clip out (not emergency), I do so while seated and slowing, on the right side, then stand on the left pedal just as I stop and put the right foot down. I do practice doing this with the left, but it is easier for me on the right.

Frankly, if clipping in or out remains difficult after giving it enough practice, and contributes to a fall or almost-fall, it's time to sit down and quantify what the problem is, and look for a pedal that is good in those areas. For me, I needed pedals that release with little or no strength, and clip-in that does not require looking down and hooking in one part or another to start. Dual sided helps too.

Of course, it helps to have good balance on the bike in general. I've been doing balance exercises on the WiiFit and it has helped me as I am normally a clumsy person.