You have a good deal of questions here. The most important one is perhaps the question about providing a moral at the end. This is rarely done, if ever. The point of being indirect is to let clients create their own meaning.

How do you maintain rapport? You establish it when you first meet clients and thereafter, clients trust you to be relevant and doing therapy for their own good. Take a sincere attitude and expect them to be working as well.

I also expect my clients to be thinking, experiencing, and working by reporting it to me what they are making of what is happening. So, they don't ask me what a story meant.

Perhaps you in need of some training and supervision as you mentioned. I don't know of any tapes on those exact issues you raised. Supervision is available for professionals (check my website for info on that). I usually expect people to have studied with me some minimum amount and read some of my books first so they are familiar with what I'm referring to by the use of terms. Otherwise, supervision sort of becomes expensive private training.

I have worked with one-way mirrors at times. But, more often with live video viewing paired with live ear-phone feedback. These have been in advanced training programs by invitation (that is, when I invite my best students to advanced training groups).

Finally, I don't know why you would need to be indirect with the point you wish to illustrate with the husband. Why not just explain your observation, ask the wife to explain her reaction, etc.? If those were just hypothetical examples, then it seems like either of those brief descriptions you gave could become fine examples of therapeutic interventions when made into stories.