Mindfulness and Effortful Study

In looking for further parallels to serious chess and martial arts training, I came across the below excerpt, taken from a Scientific American article and posted on a martial arts site.  The term "mindfulness" is often used for meditation and other mental exercises, which essentially means that your mind is present in the moment and concentrating on your task, as in Focusing on the Path.  The term used below is "effortful study" which is less aesthetic, but conveys more precisely the process involved, i.e. constantly thinking critically and taking on new challenges.  Note also the comparison with musical study, which shares similar characteristics regarding the attainment of mastery.

"...What matters is not experience per se but 'effortful study,' which entails continually tackling challenges that lie just beyond one's competence. That is why it is possible for enthusiasts to spend tens of thousands of hours playing chess or golf or a musical instrument without ever advancing beyond the amateur level and why a properly trained student can overtake them in a relatively short time. It is interesting to note that time spent playing chess, even in tournaments, appears to contribute less than such study to a player's progress; the main training value of such games is to point up weaknesses for future study

Even the novice engages in effortful study at first, which is why beginners so often improve rapidly in playing golf, say, or in driving a car. But having reached an acceptable performance--for instance, keeping up with one's golf buddies or passing a driver's exam--most people relax. Their performance then becomes automatic and therefore impervious to further improvement. In contrast, experts-in-training keep the lid of their mind's box open all the time, so that they can inspect, criticize and augment its contents and thereby approach the standard set by leaders in their fields."