I don't know all the technical reasoning behind putting bones in your soups
and stews but, I always use the bones for flavor.  You do want  a bone with
marrow.  When I make Smoked Turkey Gumbo I simmer the bones over night and
then remove and save the meat.  The broth is gelatinous when chilled.
Again, I don't know the reasoning just that it is delicious.
Mary Spillman