Curvature graph to have cv pts

Hi All, has it been thought of to have curve graph with cv pts.?That way you could tie it with the curve that you want adjusted. By then moving the graph points would also move the curve, but in a way that the curve graph is controling. Seems like a bit more control could be had in that way. Thanks

I guess instead of a diagnostics tool only, maybe an interactive tool. Could a person put a cage around it?