Vincent, I think you're being overly hard on Ed Mitchell. Yeah, his psychic stuff was just plain embarrassing but I can't say he didn't do his job well as LMP. And that's what counted.
Astronauts were selected for their capability to do what astronauts do. They were not selected because they were the people you'd like to be buddies with, marry your daughter, or (most famously) be really good public speakers.
Some were downright misanthropic, or guys you'd shoot on sight if they came within hundred yards of your daughter, or were absolutely terrible public speakers. Those traits weren't relevant to the job description.