(A) This is kind of a red herring though. The rules are not uniform. Sick patients require more protections than healthy adults. Placing an implant in someone's leg requires a more comprehensive risk minimization plan than asking someone to look at the ground for 5 seconds and then read a flash card.
(B) Is the lack of risk really self-evident? To everyone? Or just to you? Thus the question who should decide? And by what process do they decide?