All examples I've seen, and the few I've partaken in,
Therein lies the problem "the few" I applaud your love of anesthesia and your concern for the patient but there will come a day that immediate action will be needed you will not have time to "call for your supervisor" or really think about it, at that point you must be able to ACT, the second point you will in the future have a better idea of the condition of the patient and you will find yourself giving a suboptimal anesthetic because of the limitations of your supervisor.
Case in point in a locums gig in PA 78 Y/O female with a complex fx of humerus, pt had hx of aortic stenosis CAD etc. etc.
This case screams for regional anesthesia to reduce the surgical stress, need for volatile anesthetic and post op pain control. Do we, Noooo, the attending is not comfortable with ISB, so what if I do 3-4 a week at my regular gig. I am just a nurse. Suboptimal anesthetic medically directed, wow I am so glad he was there. NOT.
That is why I value Independence, I have no problems with MD's as a whole but a lot of them just are not that good as clinicians, time will tell and you will see and you will be stuck following the plan of some idiot with MD behind his name.