Pinned is a really intriguing concept.

Not sure I agree 100% with it as I can see scenarios where bumps and obstacles can cause the feet to bounce off the pedals and that would make me want to stick with clipped in.

But, the large platform for power into the crank makes sense.

Curious though, does the lack of a stiff soled shoe cause pressures in the arch ?. Could see where Plantar fasciitis might develop.