Kark, you asked one question, but some of the responses are morphing into answering a different question. The radiation oncologist creates your treatment plan, and will only accept his/her appropriate degree of responsibility for that plan if it is carried out by his/her “team” of technicians…this is professionally reasonable.
I think that your original question was related to the reason for selecting an expert radiation oncologist.
The key reason for selecting a radiation oncologist who is not a “jack-of-all-trades” is essentially the same as not selecting an inexperienced surgeon. The lessons-learned by both radiation oncologists & surgeons (or just about any other technical profession) through direct experience result in tweaks, adjustments, expertise and knowledge to their craft which cannot otherwise be easily acquired.
There is an old saying which goes something like: “Good judgment is based on experience. Experience is based on bad judgment.” Your PC radiation plan, if developed by an expert, will take into consideration that good judgment which has been gained by experience and lessons-learned from many prior patients with PC. You don’t want to be among the first couple dozen prostatectomies that a surgeon learns on, but if the surgeon is specializing in prostatectomies he will go through that learning curve much quicker than a jack-of-all-trades who does one of everything.
Mayo says it this way:
Each of Mayo Clinic's radiation oncologists specializes in treating just two to three types of cancer. At Mayo, even patients with rare cancers work with experts who are highly skilled at treating their condition. Patients should always choose a radiation oncologist based on the physician's experience with their specific condition.
If you want compassion, you can get that anywhere. If you want expertise, you likely have to go to a major center and/or teaching hospital.