No offense folks, but I call bullshit. I bench more close grip (12-14 inches apart) than I do with my hands wider. I’d say about 120%.
Principle of specificity: Your body becomes good at what it does. If you train one way, you’ll be good at that, and perhaps not so good at other things.
Wouldn’t that principle also imply that if you neglect to do something, your body will become bad at that? I mean, are you sure that its fair to that your close grip is stronger when it may be more accurate or at least equally accurate to say the your bench has become weaker, relatively?
I would wager that most people who train wide grip and close grip bench presses equally will be able to bench more with a wider grip, not only because of the shorter bar path but because of the larger involvement of the pecs. I know that when I used Westside for about six months almost all of the bench press variations I used were with a close (14") to medium (pinky on rings) grip by my strongest grip was always wide (index finger on the rings). Then again I always sucked at benching either way.
Although it’s possible, there are multiple considerations. First, there is more chance of a shoulder injury with wide grip. If you are getting heavy, this becomes more of a concern. Second, look at how powerlifters push. I think that if they thought they could put up bigger numbers using a wide grip, they’d do it. But I don’t know of any that lift with a wide grip…
I usually do encorporate a wider press when I do dumbbells, so that I can keep my chest in the equation, but I began lifting close grip barbell press in April, and I must say that I now prefer it (I did wide grip for about 12 years).