I always thought (and have observed, generally) that most right-handed males position their cock down the left pant leg, while most left-handed guys position their cock down the right pant leg. The testicles are configured so that one (the right) hangs lower than the other (the left).
I also always understood that manufacturers of pants/jeans/shorts/whatever actually left more material on the left pant leg crotch area to accomodate that most folks are right-handed. The exception to this "rule" are the manufacturers of specialty clothing items --- like the Speedo -- - which has a completely different design starting point (as tight as possible, with lots of nylon and lycra) and those tailors that offer bespoke (custom-made and fitted) suits.
In the case of the Speedo, the fit is utterly "truth in advertising" such that the exact dimensions and characteristics of the wearer's genitals are very obvious, but that is not the point of the suit - for a competitive swimmer, the Speedo trunk is usually the tightest, tiniest article of closthing that they can get away with, the premise being that the closer to being naked and streamlined, the faster the competitor can swim. In the Olympics, where the timings measure down to the one-hundredth of a second, this is important.
in the case of the tailor, he is interested in how the fitting will "drape" on the wearer's body, and thus he builds in the material - in the correct place - to accomplish this.
What might be interesting would be to hear from our younger members who "sag" their boxers such that the waistband is resting on the base of their cock, and wear extremely oversized pants. What effect does this have on the way they hang ? And what do they do to deal with a hardon ? :biggrin1: