You appear to be parroting the nonsense from Collier's "I hate Feynman" videos. Feynman gave the FLP lectures at Caltech, which were recorded and photographed, but at that time there was no intention of making them into a book. Leighton and Sands (with the help of some secretaries and grad. students) transcribed these lectures, and then lightly edited them, for use by Caltech students as study notes. These fell into the hands of publishers a couple years later, and they were the ones who proposed turning them into a book. I am now the Editor of those books. To say Feynman "didn't write" FLP may be true in the most literal sense that he did not set pen to paper, but the content is his, as you can easily verify by going to The Feynman Lectures Website, where you can listen to the recordings and see the photos of the original lectures and compare them to the book - they are the same, except for very minor changes that would be required to make any spoken lecture readable.
