I'm interested to know in what way he should be sleeping better? What are his sleeping habits at the moment and are they something you feel you can't deal with or are they just habits your GP thinks needs to change?
If you are coping okay with what you are presently doing than I wouldn't change but if it is something you are not coping with well then maybe look around and ask opinions of what has worked for different people and see what you would feel comfortable with doing.