I just saw this quote from Wayne in Roger Ebert's 1967 PEOPLE interview with Wayne, (on the set of The Green Berets
) http://rogerebert.suntimes.com/apps/pbcs.dll/article?AID=/19671008/PEOPLE/710080301Wayne grinned, "You know," he said, "all the time we were making that movie, I was scared to death someone would notice that all Hawks was doing, basically, was taking 'Rio Bravo' and sort of juggling it around a little. I played the same part, and he switched Robert Mitchum for Dean Martin, and the plot was almost exactly the same. But no one seems to have noticed."
Either Wayne was wrong, or people were stupid in 1967; I'm not sure how anyone could have missed how much of a direct ripoff El Dorado
is of Rio Bravo
(and why, btw, I had no pleasure from watching El Dorado