A much heavier emphasis on recovery. I know, I know, 27 isn't "old". You're 47 and your knees and your back and your kidneys and stuff. Still, I'm at nearly 10 years of BJJ (plus a few years of wrestling), and most of those years were not spent training intelligently, cutting too much weight (I could have been taller!), and losing a lot. Nowadays, I try to think more about my diet, my mobility and sleep than I used to.

Much more goal-oriented during rounds. When I was younger, my main goal during training rounds was to win my rounds. Now that I'm an old man, my goals are a bit more specific to technical things I'm working on. For example, one round might be a guard round focused on upper-body attacks. One round might be a passing round focused on loose passing. Specific rounds lead to specific skills.

Less drilling, more moving. When I was a lower belt, I spent a lot of time repping different moves. It was the former wrestler in me manifesting itself in BJJ. While there is definitely value to repping things (my leg locks improved 10x from repeated "micro-drilling"), I don't think this is something you need to do forever. Instead, I do more specific rounds with specific goals for myself.

Better results, but less emotional attachment to the results. Oooooommm I am a Buddha now. Just kidding. Really I just think that after a long time of being stressed about my competitions and my results, I just don't have the energy to beat myself up anymore. Today, I am a lot more focused on technical displays than I used to be.