Successful people often talk about the sacrifices they had to make in their 20s to achieve their goals. Many of the best programmers, for example, have spent long hours working on their craft.
The raw practice of ideas in combat and science needs to sometimes throw away expertise, while expertise is valuable when taking advice from different people in certain situations. Some arguments in the cosmological and philosophical spheres require a delicate balance of both approaches.
Jiu-Jitsu practitioners should train consistently, ideally 5-7 days a week, and focus on practicing and perfecting a set of techniques. Starting with 2-3 days a week is recommended to avoid injury.
Josh Waitzkin's learning system can be applied to various fields, from Jiu Jitsu to Tai Chi and even surfing. He calls it "learning the macro from the micro", where you can learn a lot about someone's skills by having them do a specific drill or task.
Sensei Seth Adams explains how to build a dojo that caters to both Olympic champions and recreational martial arts enthusiasts by creating different programs and defining clear roles for instructors.