As a rule, pawn endings have a forced character, and they can be worked out conclusively.

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.

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

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.

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.

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.

It is hardly useful if you trustingly play through variation after variation from a book. It is a great deal more useful and more interesting if you take part actively in the analysis, find something yourself, and try to refute some of the author's conclusions.