Notwithstanding anything to the contrary in these regulations, the relevant subcommittee, subject to approval by the board, may register the speciality or subspeciality of a medical practitioner or dentist who complies substantially with the requirements of these regulations and who, in the opinion of the board, is competent to practise in such a speciality or subspeciality, and the applicant shall, at the request of the board, submit the documentary proof which the board determines in support of his or her application.