I think the poster was refering to the fact that it is our own issues that make us want to become Ts. I want to become a T because I feel that my T has and is helping me. I suspect that is a reason that a lot of T's get into the field. I am not sure what the statistics on this is. It would be interesting to see how many Ts had been in therapy in the past. The clinical supervisor to trainee relationship has some aspects similar to a therepeutic relationship (according to my teacher anyways) but it wouldn't be as indepth on that individual trainee's psychological issues whatever they may be.
I don't think I could work with a psychiatrist/therapist who was a patholoical lier because I couldn't trust that person. I believe that therapy relationships on built on trust and honesty between client and mental health provider. Why do you think he is a pathological lier? If you reasons for believing this are sound, I would consider trying a different Pdoc. I just wouldn't comply with doctor's orders if I thought he was a pathological lier. I want to know that my doctor will tell me the side effects of my medication/risks/ any other potential issues.