If you can relieve the stresses that occur from flapping and coning by using a hinge (mechanical or elastomeric) why would you go to all the trouble of engineering a complex solution to a problem you have already solved?
You have to make a blade now that bends and twists enough to absorb all the periodic lift changes without transmitting them back to the mast and fuselage as well as making a control system to input that twisting when you want it to happen. Good luck, but why bother?