I don't know why the old guy crashed. The story I was handed was that "he turned his wheel too far" but that doesn't look right to me.
I didn't see the crash but I saw the guy laying in the gravel and I was about to go out to check on him, but then he got up. This happened during a cycling event with a lot of riders. After the guy got up a wave of riders zoomed past him on both sides. The guy looked a bit dazed and he walked around in the gravel for a bit until a female rider stopped to help. Leave it to the compassion and caring of a woman to take herself out of a race to help someone.
She got the guy off to the side, called the Sag Wagon, looked around in the gravel to help him find something, and then waited with him until the Sag Wagon arrived. I put the video clip on a flash drive and took it out to the woman to give to the guy as a souvenir. That's when the woman told me that the old guy's story was that he turned his wheel too much and crashed.
I didn't see him turn the front wheel too much. It looked more like he hit the front brake to hard as he hit that rise in the pavement. Physics can be a beotch sometimes.
From what I could see it wasn't enough of a turn to do that. Then there's the question of why he would turn it in the first place. As a famous comic once said "the road was going straight, I was going straight" (Bill Cosby driving back to Temple U while drunk).
If the front wheel was turned perpendicular to the direction of travel then it would have been like slamming on the front brake, but that obviously didn't happen. I think that the old guy riding the bike was just a bit confused, and perhaps he made a random statement not knowing exactly what happened. It's not uncommon for people to not know exactly what happened when things go wrong. But the question remains, why did he grab his front brake so hard? He just came across a bridge with a nice concrete deck, then he crossed over a small amount of gravel before going onto smooth tarmac. At the point where things went wrong he was well away from the gravel and was on smooth pavement. Well, at least physically that's where he was but I don't know where he was in his mind. I think he just over reacted to something and grabbed the brake. After grabbing the brake his front wheel turned a bit and maybe he somehow thought that was the cause.
One of the reasons that I gave him the video clip on a flash drive was so he could see what happened, analyze it, and perhaps learn a lesson. I've found this kind of info quite valuable when analyzing my own motorcycle racing failures. Often what I thought happened was not what was shown in the video. It's just how the human mind works sometimes.