This is not a competence argument. Generalist accountants are not weaker technically, they simply do not see enough doctors for the medical patterns to become obvious. A specialist reads a pension savings statement and knows immediately whether the input amount looks plausible for that pensionable pay, reads a locum engagement and knows which IR35 factors will decide it, and reads an expense schedule and knows which items HMRC has historically challenged for doctors.
The difference shows up as things noticed early rather than repaired late. Unused carry-forward from the three previous tax years before an annual allowance charge crystallises. Forms A and B filed so that locum sessions actually count towards pensionable service instead of quietly falling out. A basis period reform adjustment modelled before it lands on a payment on account. An incorporation modelled properly rather than assumed, because for a partner with only NHS income it is usually the wrong answer.
There is a plainer benefit too. You will not spend the first meeting explaining what superannuation is, why your practice year end is not 5 April, or why your indemnity subscription is a business cost. That vocabulary is already shared, so the conversation starts at your position rather than at the definitions.