The Bell team, who had no idea how to design a super sonic aircraft at the time copied the design
The Bell team did not copy the design. You've been listening, it seems, to the garbage sprouted by Eric "Winkle"Brown. The Bell aircraft owed absolutely nothing to the M.52. In fact the American who was briefed on the M.52 commented that the Miles had some interesting innovations, such as biconvex section and one piece tailplane, but had nothing of real interest to offer and little need to follow its progress.