Well thank god I have never had TOFP *knock on wood* but if your form isn't almost perfect then that could easily be a problem. Also you will walk different in trainers which will hurt your form. Have you ever tried to wear your VFF to your racket sports? Also if you can't wear VFF to work I would buy a pair of minimalistic shoes such as the Merrell Glove series or the New Balance Minimus. Those minimal shoes will help a great deal do to the thin sole and zero drop heal (Minimus has 4mm rise).
Touching up on the Bikila/Trek question. I only have the KSO's so mine do not have any thickness to the sole. 1mm is significant if you walk and run barefoot all the time but to an untrained foot I don't know if they'll be able to tell the difference.

