People learn how to adapt. For many it's a learning by doing thing.
I'm not saying that you are wrong. I'm just sharing my personal perspective on how I learn because it shows that it's different than what you are saying.one
I don't learn how to adapt. I take what I already know and apply possible solutions to see which one works better to address the changing system. This is not a learning situation because if you don't have the solution already then you can't adapt. Adaptation = bringing existing solutions to the table. These solutions are based on existing skills.
If the solution is to use better footwork, then you won't learn that better footwork in the heat of the moment. This is how long he had to learn better footwork. He had the same amount of time to learn better defense.
The reason he couldn't adapt is because those skill did not exist. Because those skills didn't exist (he did not learn them) , he could not draw from them and use them to adapt.
I've yet to meet anyone who didn't have a learning curve on how to appropriately manage their stamina the first few times they entered a competitive 'fight' regardless of the sport.
You have now. I learn how to manage my stamina through sparring. Keep in mind that I see competition where a Winner and Loser exists. I see stamina like running (because I ran track and cross country). I learn to manage stamina through training. I don't wait until competition day to try.
For example when I gassed out at the Sanda school. I took note of how tired I was getting, I had to make adjustments, and then pushed through and all of it sucked. As a result I changed my training so that my stamina would improved. I did a lot of 1 minute sparring rounds. If I had to fight 3 minutes rounds then I would do a lot of 5 minute sparring rounds. In my current training, I try to stay consistently active during the workout. The most rest I get is 15 seconds which is more of a transition point. When sparring I try to do a Round Robin so that I get fresh bodies to spar against every minute. This transition time is around 3 seconds.
If I need to train stamina for hitting my hardest then I take it out on the heavy bag and I do my footwork around the heavy bag. By doing this, I can be ready when it's time to Win or Lose