I like James stuff but can't say I agree whole hearted with that article.
The first two points are important but his placing too much emphasis on it, albeit it's important but technique is what makes grip. Ok running slippery boots won't be ideal but "flat specific shoes" are not needed plenty of guys not using 510.
I think James recently picked up 510 for a sponsor too so take that as you will.
The ideal of middle foot intrigues me but it goes against what I have felt on the bike, also can all the companies and professional riders get it wrong, I'm sure they have tried various foot placement.
Deadlifts and I believe squats are a heel driven movement, can't say riding on the heels is ideal, they are also a straight up and down movement,riding shouldn't be a stomping up and down on the pedals. You need to move your legs in a circle with the pedal not smash them so I'd have to disagree that deads and squats are the same movement.
Having a mid to back foot position also limits you ability to rotate the pedals back, this is more a issue of dh or mtb where steep declines are involved.
James is great and does lots of good stuff but this is one article I can't 100% agree with, albeit his a professional so I'm sure most will disregard this opinion but I figured I'd weigh in anyway