Puts me to mind of a Red Skelton story--

This sky-diver has jumped out of the plane, and his main chute failed to open. When he pulled the ring on hus back-up chute, nothing happened. As he was falling he saw another man zooming up at him from below. He yelled, "Do you know anything about parachutes?"

And the other man yelled back,
.
.
.
    .
    .
       .
         "No! Do you know anything about Coleman stoves?"