Frank is the AHJ here and he has the duty of enforcing the NEC per 90.4.

If nothing else, Article 527 may be another way to address the need for the protection.

PS: A defective electrical instrument could carry current, and could be the cause of an electrical accident, trust me!

Also, some of the members here send me an email message and most of the time I include my reply here so all can see where I am coming from.

Joe Tedesco, NEC Consultant