REMINDS ME OF A TUBE TEST METHOD WE USED TO TEST VACUUM TUBES FER tvS and radios........ you dropped the tube on the floor, if it breaks, it was good.....!
Had my 7D MKII with a Tamron 18-270mm on it and was busy shooting a football game. Half time went to bathroom and slipped on the wet floor and down I went. Lens would work from 35mm-270mm but not below. Glad I have insurance on my camera gear. Called the insurance company and told them what happened. Received a check for more than I paid for the lens when new. I tried dropping it again with little luck. So I purchased the 18-400 mm and now check the floors.