I quite agree. I wouldn't interpret his statements as he "doesn't know how" but that he is unsure how to be helpful to you, because like everything else in therapy, it's individual. It seems to me that telling other people they don't know what they are doing is likely to push someone away or decrease their motivation to assist you, or other sabotage an ending that is right for you.

I think if you let him know what you'd like from him or sketch out an outline of what termination would look like for you, you'll move things along.