I think you will find they did. In fact, even Cartier Bresson himself took several shot at different angles to come up with the masterpieces we enjoy. (See his Scrapbook publication) I don't know a single pro photographer who relies on a single shot from the camera to make the final statement.''
Don McCullin actually guessed exposure if he didn't have a meter. See interview here:
http://www.bbc.co.uk/radio3/johntusa...anscript.shtml You have to do what you have to do to get the shot.
I can set my camera to either, but I prefer, and have set mine to exposure lock, as I work and expose that way most of the time. I only ever use centre focusing, as that is also the way I have worked for years. I prefer to focus on the subject and recompose if necessary.