Yes, many men measure the size of their procreational organ. They do this because there is a widely held social belief that to have a large member is a good thing. It means (in some peoples minds) that they are masculine, can pleasure women well, but more importantly they are 'better' than other men with smaller members. These opinions of superiority are sadly mistaken. Many of the people who measure themselves and find they have a member 5% larger than 'normal' or even bigger feel satisfied that they are superior to men who only have normal sized tools. However this does not take into account how the member is used, many girls will tell you that they much prefer a smaller member used carefully, with sensitivity and consideration than a big sausage used roughly and selfishly. Think about the size of peoples heads, do people with large heads show more intelligence? no, of course not. Do people with long fingers play the piano better? No, they don't.
With the huge amount of porn now available a large proportion of men see larger than average organs being used with apparent great effect. Unfortunately the porn pics and videos are just unrealistic shams and bear no reality with the normal love making practices of the majority of the population.
But this doesn't stop the sad men dreaming and imagining what they could do or might do with their 'slightly larger than normal' members. The bragging of course is just a big bluff, like a baboon flashing his teeth or or a gorilla crashing through the bushes. Take no notice of the bragging, just think quietly to yourself 'what a sad and anxious man'.
Remember the Rule of the Street No.3 the bigger the mouth or the flashier the car the more inferior the organ.