I did a rotation with a private group at a community hospital. Up until this year, they had been an MD/DO only group. They hired a recent CRNA grad and began "training" him and supervising him one on one until they felt comfortable with his skills. They do a lot of U/S guided regional anesthesia and they started training him in that too. For this group, (and another local private group) their decision to hire a CRNA was purely financial. I really don't think they are looking to sell out the specialty to murses, they are trying to cope with the decreases in reimbursement.
I believe financial gain is probably one of the main reasons why many groups continue to supervise and train CRNA's. For many of the recent grads and those of us about to enter the field, supervising CRNA's seems to be a practice of career suicide. However, the guys looking to retire in the next 5-10 years probably aren't too concerned about selling out the field as they are about securing a sound retirement. I think this is one of the biggest problems we will face in this war.
Why would an older physician who supervises CRNA's want to support a study that would ultimately hurt his pocketbook if the results show that the CRNA's are unsafe and incompetent?