I disagree about flyes. While I don't do them because they're useless to my goals and I feel they place too much stress on the shoulder joint, I've always felt that when I did them I really worked my chest very well. After all, the function of the pectoral muscles (if I recall correctly from camaro I believe) is to do that exact motion (like hugging a tree). This means they're actually more in play during flyes than during, say, a BB bench. If you lose tension at the top, the mind/muscle connection usually comes into play because you can simply squeeze the muscles more during the top portion.