Not to criticize John Denver's airmanship in general - he was obviously an accomplished aviator - BUT for this specific flight and leading up to it, he showed less then perfection, rather negligence:

John Denver did nothing for aviation. He had lost his license for crashing his Porsche under the influence of alcohol. He had no license for cars or airplanes.

 

If you see vice grips being used as a normal part of an aircrafts equipment, what comes to your mind? I have got to buy this airplane? No, you don't think that at all.

 

If you loose your license, do you think, I'm famous, so nobody will notice me flying again with no license? No, you wouldn't.

 

And if you are out of fuel because you chose not to add any, will changing tanks with your vise grips cure your problem? No it won't.

 

 Whatever John Denver was, he was not a pilot. He raised our insurance rates. He killed himself, and the world lost the benefit of his talent, and he destroyed his family. He destroyed what could have been a nice airplane. He made it more difficult for all of us to fly. 

 

Lynn E. Hanover