I agree with Wejo's statement that Jones and Montgomery are free to work with Charlie Francis if they want. His article in Testosterone magazine certainly showcases his up-to-the-minute knowledge of how to dope and not get caught... so at least we know what HE brings to the deal.
But, what's also true is that companies (like NIKE) and organizations (like USATF) can decide that they don't want to support athletes who take such a cynical view of the sport that made them rich that they are willing to work with coaches like Francis.
Of course, I realize that plenty of other coaches also provide drugs to their athletes, and that Francis differs from them mainly in his open-ness in stating that he cheats like everyone else. But before anyone bothers to say "I admire his honesty", I'd just say that being shameless isn't the same thing as being someone to respect.
So, Nike, have the balls to drop them (even though they are REALLY fast) and put the money into athletes who have some respect for their competitors.