Yes, proper placement and intensity was often part of the art of the whack. Someone untutored in the art could shake a malfunctioning device, kick it, beat it up all day without "fixing" it. Finally in desperation one would have to call maintenance. The guy from maintenance would come up, take a look at the symptoms, maybe ask a few questions, then give it the right <thwack> in the right place and there you go, instant fix. Guess that's why he was paid the big bucks.