I wonder if he could adjust the valves on a car by reaching up the tailpipe?
There was once this successful gynecologist who decided to quit medicine and become a mechanic. He went to the top auto mechanics school, enrolled, and started taking a class on engine repair.
At the end of the class, the final exam involved tearing down and rebuilding an engine. A few days after taking the exam, the doctor checked his grades and was dismayed to see a score of 150 percent for his final. Surely, this was some sort of typo!
When the doctor caught up with his instructor, he asked about the grade. The instructor smiled and explained "Fifty percent of the grade was for the tear down. You did that perfect, so you got every possible point. Fifty percent was for the rebuild, which you also did perfectly, giving you another fifty points."
"But what about the other fifty?" asked the doctor, distressed.
The instructor smiled, rubbed his chin and replied "Well, I'd never seen anyone tear down and rebuild an engine by reaching up through the exhaust pipe, so I figured that ought to be worth at least an extra fifty points!"