I think I know why it really is so damn funny. See, there are two reasons we blush when someone asks us "where it hurts," and only one of which is tied to having the dangling, vulnerable parts in question. The main reason we blush is because in that moment we're finally forced to acknowledge the special brand of stupidity that inevitably comes with having those parts, because chances are, we were asking for it. Those two things are what makes "man pain" so easy to laugh at, and I, regrettably, happen to have both the parts and the hair-brained idiocy that would cause them to get slammed by something. But see, I only find it "funny" when it happens to guys who are not me, so there's nothing funny about the following story (warning: you may find the following story funny if you're not me).
This is how I lost my virginity to my bike. The neighbor two houses down used to allow the girl next door and my brother and I to ride our bikes in their long driveway. We spent many an afternoon riding long circles up and down it because we were too wussy to ride in the streets with the cars and the threat of instant death. Somehow, we were supposedly safer if confined to the driveway than we would be on the (somewhat) busy suburban... back road, if that makes sense. Unfortunately, the protectionist driveway culture of the 90's wasn't counting on my temporary "lack of brain" syndrome, and once when I was probably about nine or ten, I got so lulled into watching the asphalt pass below my pedals for a time that the tar failed to protect me. I wasn't watching where I was headed.
BAM! It came to a sudden halt and threw my body forward like those crash dummies in the commercials. My butt slid off the seat and hurled my crotch (and all it contained) right into the bar beneath the handlebars with extreme prejudice, and the two of us, bike and I, fell over together on the asphalt. As my brain kicked back out of its haze, I realized what I'd done in my trance. I had slammed into the back bumper of the car sitting stationary in their driveway! That's right. I hit a car that wasn't even moving. My first thought was "I hope nobody saw that." My second thought was "oh no! Not good! NOT good! Ow!"
It was the most nauseating "man pain" describable. My vision was cross-eyed. Drool trickled from my chin. I feebly threw my hands between my legs as if trying to hold whatever was left down there together as I staggered forth, soon dropping down to all fours. I could have puked as it shot right up to my stomach. There's no walking that off! And to top it, there was no "oh he's hurt!" There wasn't even a "are you okay?" or even a condescending but sympathetic "...ouch." There was nothing but "Hahaahah!!," "how does that feel?" and "wow, that was stupid..." Meanwhile I couldn't even freakin' SEE, never mind stand, and damn was it humiliating, but whatever. "No I'm okay..." I squeaked out. Yeah right. Even when my mom found out about the incident later that evening, after I'd managed to wobble home, all I got from her was, "haha, you weren't planning on having kids one day anyways, right?"
Unfortunately, the same force that propelled this boy to slam into a parked car on his bike also prevented him from learning anything from the experience, as more bike accidents were sure to follow, but I did learn that "man pain" really does hurt and that it ... really is freakn' hilarious! I mean, the "oof!", bend-over, the crotch-grab, the wince, the rolling on the ground ... it's good stuff! Now don't get me wrong, I don't recommend, or condone, anyone going walking around aiming for the sweet spot just for target practice (there are less violent ways of getting a laugh!), nor do I agree with bullying down there (seriously guys?), and girls get a pass at doing it for self defense... and whenever they need to prove a point. But if it happens by accident (and it will), laugh only if it's funny. Otherwise, call 911!!