As I've said, the director's role is one of the hardest to define. No two directors are the same in how they approach a play, and directors often approach different plays in different ways, depending on the type of play, available time, and experience level of the actors.
Some directors come into rehearsal with a very clear picture in their mind about how the play will look when she's finished. She has the blocking all planned out ahead of time, very specific ideas about the actors' performances and the various design elements. In the extreme, this can be an unsatisfying experience for the other artists because the director is barely engaging their creativity. Everyone becomes puppets for the director to control. On the other hand, if this approach is done with a certain sensitivity, it can result in the realization of a very strong, clear singular vision. You know this director's work when you see it.
Other directors are looking for as much input from the other artists as possible. They keep their own ideas out of the conversation until everyone else has had a chance to share their thoughts about the project. Ideally, this leads to a great collaboration, where everyone feels heard and feels like they've made an important contribution. Again, in the extreme this can lead to a feeling of rudderlessness, and the production can feel like a big, amorphous mess with everyone going in their own direction, but when done well, this approach leads to a situation where the whole truly is greater than the sum of the parts.
The best directors (in my opinion) combine both of these approaches, and Jim is one of the best directors I know. He comes to rehearsal with very clear ideas about the play, and maybe even a few specific images in mind, but he is constantly looking for input from the other artists, and he is quick to change his mind if he sees that they have an idea that works better than what he thought of.
Jim has this ability to suggest something to an actor that makes it seem like it was the actor's idea - and in a sense it is. Jim is extremely good at picking up the subtlest impulses from an actor and drawing them out. So an actor will be going along, trying to find their way though a moment, and Jim will notice that an actor started to go in a certain direction (either physically or emotionally) and Jim will spot it and say, "there, that impulse you just had, why don't you go ahead and play with that, flesh it out, make it more specific." Jim picks out these moments because they resonate with him and because he knows that since it came from the actor organically, it has a better chance of being authentic, as opposed to something layered on from the outside. It's a stronger choice, because it came from the actor - Jim picked it out because it is also in line with his vision for the play.
Jim also has a very gentle persona, which in my opinion, is exactly what you need in a rehearsal hall.