I do think this particular topic could be made simple.
Unfortunately the only surveys done are singular in approach and I have only seen a few and all of them had a very small sample size.
Equally unfortunately is the angle almost all threads wind up taking with people speaking their singular opinion that is without thought and usually just wishful thinking.
Size matters on all levels - mental - on many levels, visual and physical.
What is wrong with that? A woman's erotic thoughts and responses are beyond hot!
I believe it would be very, very healthy for guys that are average to average plus to learn that YES his current partner had bigger and in some ways it was better simple because....
Then he could free his mind to learn what else turns a woman on and gets her to return to his bed. He would find out the list is lengthy and almost everything on it is within his control, for example: be sensual, treat her like she is your very own princess that you cherish, make an effort to be fit, work hard to provide, clean the house (yes this is on the list, one of most sexually eager woman on my friends list has said seeing "her man helping her with the house gets her going)....
What happens just about every time:
A guy really likes a woman and wants to be special for her. One of questions he has is about his size. He hears "it is not the size of the boat it is the fight of the dog" (deliberately mixed up a couple one will hear) and thinks "oh good". Then he starts remembering the roommate of his that was very hung and without effort in real demand for booty calls and that one girlfriend that had a hard time not visiting that ex for booty calls and finds out through the grapevine one of reasons she couldn't get over the guy was that he was hung like Billy Glide. Now the issue is really in his head, now magnified since someone is fibbing and hiding things and he wonders why now presuming it, size, is the end all and thus some type of secret that has to be kept as said.
Bigger is better!
So is being fit, being kind, being a sincere listener, being trustworthy, being a good provider, showing kindness... the list goes on and all of them are better too.