It takes time to get to that point. If you keep practicing controlling what you say, eventually it becomes a habit. It was so hard for me at first, but now I don't say much about stuff other than the kids and some small talk sometimes.
With the MLCer, you may find that being quiet and listening DOES cause them to open up to you at times. I have found that. It doesn't happen too often with regards to the deep stuff, but every once in awhile I get a peek into what is going on inside of his head.
