I used to refeere on very muddy pitches in my bare feet. I could out run all the players on those days. No build-up.
If I were you, I’d go barefoot as more of a drill than a running style. I am very flat footed and pronate severly, so I wear orthotics in motion control shoes. That helps prevent knee problems, back problems and other problems. E.g., flat feet tend to cause your hips to rotate and your spine to flatten (reduced curvature). If your hips rotate and the hip muscles become inflamed, they can pinch a nerve. I know, because this has happened to me. Just run barefoot on grass for long enough to help your form, but not for real mileage.
Shut up and eat your box of chocolates, Forrest. 
Yeah, Nike creatd the NikeFree to silmulate barefoot running with protection for the bottom of your foot. (the website has a lot of info) I’m really intrigued by it; I like the idea that you use more muscles with a less padded shoes. But I haven’t tried it yet.
Bawahahaha Kinda stepped in it didn’t I? he he he :smack: