I'm not sure what everyone was expecting. The frontal area of feet varies between cyclists and through the pedaling cycle, but it's it's in the 4 to 7% range. So all you have to play with is the improvement on Cd of that tiny area. Even if you improve it by 50%, which is huge, your watts savings are caped at around 3.5%.

With something like a shoe that moves around through the stroke, it can never be quite clean, so texture plays a big role.

If I were to design an improvement to this shoe I would first try three beads/ridges 2.5mm thick, spaced by 5mm apart running in an arc from 1cm off the side of the shoe at the front to where laces normally stop at the top.

I think this is the most aero shoe out there, or it can be with a few tweaks. I will be buying a pair.