Garage years I agree. However if you initially allow some trim rotation assuming the STS system is operating. Then when you feel the aircraft coming out of trim you identify the problem as a runaway stab. The memory items that exist do not state as you recommend. They state Disconnect AP/AT if engaged and if it continues then stab switches off, if not engaged switches OFF. Seeing that no MCAS memory items exist then they use the most relevant which is runaway stab, where no attempt to electrically trim aircraft first exist.