I think it'll be a disaster waiting to happen! A DA II does not and will not have the appropriate backgroung to perform subgingival or supragingival scaling! Who is going to stand there and make sure the pocket does not exceed 3mm? What about  the patient's MEDICAL history prior and while treating the patient? Hygienest go through rigorous dental training and allowing DA's to perform their  duties is a "slap ' in their faces! I, for one will NEVER allow this in my practice. One must consider the liability of it all and who will be ultimately responsible if a mishap where to happen....