Just to be clear; it is impossible to assure a mains supply power connection, which is secured by a single screw acting on multi-stranded wire, will provide a constant low impedance during the life of the equipment without the use of a crimp or ferrule.
Omitting such an assured connection means the electrical equipment would fail to meet safety requirements and the duty of care required by legislation. (For example, supply continuity may be critical to the safe operation of medical equipment.)
Take any appliance (medical or non-medical) fitted with a rewireable mains plug straight out of the manufactures box and open the plug. You will always find the stranded wires are fitted with a crimp. If 100% of every electrical appliance manufacturer have made an assessment and come to the same conclusion then why should professionals such as those using this site think differently?
