Emotional instability can be one of the factors giving rise to a failure by chess players in important duels. Under the influence of surging emotions (and not necessarily negative ones) we sometimes lose concentration and stop objectively evaluating the events that are taking place on the board.

Often you will find the opposite situation. The author seems to have interesting ideas, but he is not able to illustrate them with decent examples. If a grandmaster is commenting on one of his own games, then there is usually not any problem: his general thoughts are closely tied up with what is happening on the board. But as soon as he starts writing an article or book on a different theme the difficulties begin, as he may not have suitable material to hand.

I do not know to whom the aphorism 'There are no sound studies, only ones that haven't been busted yet' belongs, but it has measure of truth in it.

In positions of strategic manoeuvring (where time is not of decisive importance) seek the worst-placed piece. Activating that piece is often the most reliable way of improving your position as a whole.

Black is now in desperate need of a good idea. Or, to put it standard chess notation, +-

It is very important to learn to weigh up objectively (or assess intuitively) the totality of the competitive and psychological factors.

I feel that it is no less interesting to be a trainer than to play oneself. I even take greater delight in the tournament successes of my lads than I do in my own.