How to change your thinking 'mode' during a chess match

The opening, middle game and endgame are different in their own rights, but I recently came across a great piece of advice by GM Matthew Sadler in his book Tips for Young Players. Sadler recommended that when you reach the endgame, get up, grab a cup of tea and then come back to the game. This way you will have calmed down from all the excitement of middle game tactics to think methodically enough to play the endgame without rushing.

There is actually legitimate neurological backing for this advice. In her book A Mind for Numbers, Barbara Oakley pointed out that in one sitting of intense study neurological activity is focused on a very local area of the brain, but when you take a break and think leisurely about a problem the neurological connections diversify. She described these two modes of learning as "focused learning" and "diffused learning," respectively. And her claim is that you are more likely to find the right answer when you take time and switch to this "diffused" mode, much like how people in history have come across solutions to problems after a good night's sleep.

So going back to grabbing a cup of tea, if you distance yourself from a position in a game, or a puzzle for that matter, you may gain stumble across a solution you were previously blind to. I feel this advice is gold. Granted, with quicker time restrictions this is not really possible, so this advice probably applies only to classical or correspondence games. Interestingly, researchers William G. Chase and Herbert A. Pick found that grand masters and beginners alike consider the same number of solutions or alternative moves (The Grand Master's genius). Obviously Grand Masters see much better alternatives than beginners, albeit due to their ability to see in "chunks" or because of pattern recognition. But is it possible that we could see better moves by taking a step back and switching from a focused mode to the diffused mode?

IM Levy Rozman gave great advice in his Youtube video Stuck at Chess @GothamChess: don't play more than 15 puzzles a day... max!!! This is solid advice intended for any impulsive player, such as myself, who does not take sufficient time to think through the alternatives. With online puzzles this is only harder, because it is so easy to just lock in one's answer. This is why IM Kostya Kavustkiy recommends using puzzles taken from books in his video "Why Puzzles Books are Better than Online Tactics Trainers" @IM Kostya Kavutskiy.

GM Matthew Sadler's advice resonated with me, as I had already incorporated in over-the-board games, in which during the opponent's turn I would purposely distract myself either by sipping tea, whiskey or looking around to take in my environment. Personally, I feel it helped me relax and avoid premature plans. What was new for me, though, was utilizing this technique upon reaching the endgame. Going to back to that quote by R. Spielmann, I feel that quote could be said better as: 'play the endgame like a mathematician', because the endgame involves a fair degree of calculation. But the sentiment is right. To play the endgame like a machine... without choking... one must play with cool head and a slow hand, so it sounds intuitive to reach the right state of mind; hence, the diffused mindset.

P.S. Chess is a blood sport and "revenge is a dish best served cold!"