Well, Photo-flo is a surfactant that is used to make water adhere less to the film (lowers surface tension) and prevent spots. Since the fixer is washed before drying, the film is still vulnerable to damage.
I use Peter's patented Photo-Flo application technique and it's one of the best tricks I've ever learned. I use a spray bottle in which I put some properly diluted wetting agent. It takes very little photo-flo. Being a bit of a clean freak, I sanitized all my equipment (spray bottle and graduated cylinder) with some alcohol before mixing it all in order to prevent bacterial growth in the solution. But that was probably going too far.