I'd like the author to explain why my wife felt pain in her feet when wearing sneakers and pedaling with platform pedals, but didn't feel pain when she switched to a cycling shoe with cleats and eggbeaters.
I've also seen people riding with non-cycling shoes on platform pedals, and their feet do flex down, so his claim that the foot tenses up and stays stiff on its own is BS.
He may be fine "pedaling free", but I'm perfectly happy with my clipless pedals and cycling shoes.