This is the age old question: Is it the size of the wave or the motion of the ocean that ultimately makes the difference?
Humans have the largest penis size of the primates, which would seem to suggest that large size is some kind of evolutionarily selected trait for humans. It could be that the shape of the penis, which is designed to "scoop" any rival's sperm out of a woman's vagina, is an influencing factor. A longer penis will do this more effectively and therefore increase the chances of passing on the genes, large penis and all.
Furthermore, pleasure could actually have less to do with it than you might think. Fewer women can achieve orgasm though vaginal penetration that through clitoral stimulation, and there is some evidence to suggest that the two types of orgasms are actually completely different things as they use different nerves and affect different parts of the brain. Even if you are one of the lucky few that gets off from vaginal stimulation alone, the G-spot is only about one third of the way into the vagina. You don't need a monster to hit that.
Studies have shown that how attractive straight women find a naked man actually has more to do with how in proportion his penis is with the rest of his body, as over-exaggerated features on anyone can be a sign that there is something wrong.
Studies have also indicated that female mate-selection is actually based on lots of other factors, with penis size playing a very minor role. It increasingly looks like the "size" question is one that generally preoccupies men much more than women. So, gents, even if you worry about the size of your assets, the chances are that she's not even thinking about it, she's probably more concerned with the bloke that's attached to it.
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