Just positional change won’t give us good result, but less muscle contraction or adequate recruiting of the muscles will. This is through teaching experience.
In kinesiology there is a term ‘postural control’, and it includes both its position of the body and muscular activity for supporting the body. However, people will think of just position from the term ‘posture’. So, I usually use the expression ‘the way of supporting our body’ instead of ‘posture’. If somebody know the single word to express ‘the way of supporting our body’, I really would like to know it.
By the way, muscular activity will still be affected by position of the body (or body parts). In the lesson I also teach advantageous positioning of the body (body parts). Then, I ask clients to release excess muscle contraction (mostly come from excess co-contraction), in especially the abdominal muscles, the neck muscles, and the muscles around the hip joint. I put more emphasis on the abdominal muscles, which is a little different from ordinary AT approach. This is because they affect more of our functions.
I somtimes tell clients that don’t think like changing the position of the body is goal or final objective. It’s for our adequate and minimum muscle activity. Don’t finish with changing the position but finish with releasing action. FM suggests “Head forward and up, and release the neck tension”, and it is right.