Cardiologist and the Mercedes Mechanic.

[stewart]

A Mercedes mechanic was removing a cylinder head from the motor of an S-Class when he spotted a well-known cardiologist in the reception.
The cardiologist was there waiting for the service manager to come and take a look at his car when the mechanic shouted across the garage,
"Hey Doc, want to take a look at this?"
 
The cardiologist, a bit surprised walked  over to where the mechanic was working on the big car .....
“So Doc,  look at this engine.
I opened its heart, took the valves out, repaired  or replaced anything damaged, and then put everything back in, and when I finished, it worked just like new.”
The  mechanic straightened up, wiped his hands on a rag and asked, “So how is it that I make £24,000 a year and you make £300k when you and I are doing basically the same work?”
 
The cardiologist paused, leaned over, and then whispered to the mechanic....

[Nic]

...try doing it with the engine running ?