Very nice demo and thanks.
I do have a comment and question
The times that I have made cockbeads, I would make rabbett on the side of the drawer fall short of the dovetails. I can see the advantage of cutting the rabbett into the tails; more bearing/glue surface for the bead.
Do you ever make the side bead pieces full thickness, i.e. completely cover the dovetail? This of course hides the joinery which can be a plus or minus depending on one's skills at cutting dovetails. However it makes mitering the beads slightly easier.
Howard Steier