Just had a thought about this. Could you use some plain backing fabric and quilt the whole top, leaving off the binding.
Then once this is done make it up like a duvet cover with fasteners along the bottom.
The top can be quilted however detailed you like it, and the back is untouched as he wants it, and unless he looks he won't see the fastening.
Also, when it comes round to winter or really cold nights, he has the added bonus of being able to add a duvet into his quilt. :wink: :oops:
Just noticed this idea has already been posted.