This would certainly be an option; however, it's difficult to pull off successfully. The responsibility matrix would have to be extremely clear before proceeding. It sounds simple to have one team create and install the responsive theme while another team only does the backend development. The real problem comes when you understand that a theme is not just "installed" and then it just "works." It's more like stitching a blue blanket (frontend) to the face of a red blanket (backend). Someone has to do the "stitching" and be responsible for it in final testing. A lot of development goes into taking the backend features and functions and "punching" them through the frontend store to work correctly.