Yes, that should work just as well as long as you are maintaining the same hight at the back of your head. Jaw tension definitely feeds in to neck tension and often beyond that too. Most who have jaw tension also have tongue tension- it comes from literally holding our tongue and clenching our jaw to keep from saying what we know we shouldn't. Feel free to PM me if you have emotional experiences from the tension release. I am trained as a movement teacher for actors and am used to dealing with this sort of thing. It will make you feel better on many levels I think.

Have used a flat cushion the last couple of times and my neck does feel less strained than with the books!. I think that im starting to become aware of my jaw tension as i can feel im pushing my tongue to the top of my mouth!....i can be quite a stressed person, which is a battle i think im slowly starting to beat but its hard to change a habit of a life time!.

Thanks again for your advice, i will let u know if i start reacting strangely!