It would be hard, at this point, to have faith in the same fitness person when you keep getting injured, particularly when they've admitted they've used the wrong approach twice now.
So you get some new fitness person with a new set of slogans and ideas, even if they're the same ideas repackaged, and it would be much easier to follow their instructions to the letter without second guessing them. Tennis players seem to do it every few years, despite being very successful with the people they're using.
It's about confidence, not competence. The Freo people could still run the show but it might be good if the script is being written by someone Bennell and his management pick out rather than hearing the same voice all the time.