I can not imagine that this experiment will help to grow people's feet. Assume the possibility of this action is also not possible, because the time of development of the frog's organism is much less than that of a person.
It might, think of it like experimenting on rats; they may be very different than people, but it allows scientists to begin experimentation until it is somewhat safe before they try on people (or more person like animals like monkeys or pigs).
Maybe in some far far future that could be possible. If you alter human gene and mix it with frogs or what ever animal you want, i know i would not like to be that "human" . I think that in that moment, if we take under consideration that it is possible, will would stop being humans as we know, we would evolve in totally new specie. But back to reality, its not possible, because if it was humans would evolve to that point till now.