Well there is, It's because you were mixing up the cross country and road work. Too much road work is bad as it causes impact injuries and the uneven surface of cross country can cause all sorts of twisting and turning pulls and tweaks (some that you won't even feel) Your knees are a weight bearing joint and one of the most important in your body, too much and it will cause wear and tear sadly.
The rest of the team was also running cross-country and doing roadwork. More than me, in some cases. They didn't get stress fractures.
I do know all about the wear and tear problem. The knees were going by age fourteen. Wrestling is very hard on knees, and my family's knees suck. My father and my uncle both did for one of theirs. The ligaments are fine in my case, but there's not much cartilage left. I can still hike long distances, but roadwork isn't an option any more. It hurts way too much.
The theory is that the stress fracture was a compensation injury. The knees were toast, so I was probably leaning back too far as I ran to alleviate the pressure, which ultimately resulted in some jerk with a burning matchstick jamming the thing into the back of my knee at seemingly random intervals for months on end. I couldn't see him, but he and his matchstick were definitely there.
Then I went and wrestled all season on the thing, which meant it took another year for it to finally heal entirely. It was my senior season, so I wasn't about to sit that one out.
That's just a black swan moment you describe. Most other people are like the other wrestlers: they play sports and they get injured and it shows up immediately. Gbamin (as I oultined above) had a record of muscle and joint injuries. It was there in his profile.
No way has there been a rigorous medical for Gbamin. Brands was desperate to get a Gueye replacement in. Corners must have been cut.
I have a lot of black swan moments. I seem to be at the center of some bizarre fate nexus, which I suppose beats the tiny thundercloud.
I don't recall Gbamin having an injury record that stood out. He had a few short-term ones young, and old Gbamin was probably going to be more Iniesta than Cal Ripken, Jr. as a result, but I didn't see anything in the data series that gave me pause.
The "no medical" thesis is interesting. It could be that we have a lot of injuries because the durable players sign for clubs like United, and we get the guys that are talented but can't pass a good medical. I tend to think that the problem is that we're always on a thin squad and we flog the horses too hard, which then perpetuates the problem. Keane seems to be hard to break. The rest, not so much.