Pretty cool design. I think you would still need some gusseting to prevent racking. There are several designs of bed rail hardware that pull up very tight.
If you add anything to the mating parts of a joint, you'll still will have movement, but it may be more quiet. Gusseting would be a triangular brace at a 90° intersection preventing movement.So basically a design like this is not possible? What if I were to put padding between the connections in the wood, this would account for shrinking and would muffle the squeaks.
And I looked up what gusseting and racking are. Where would this be needed? On the head board?