It is not possible to become a great player without having learned how to analyse deeply and accurately.

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

Training in analysis (like any other form of chess training) should be treated very seriously.

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.

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

It is not possible to become a great player without having learned how to analyse deeply and accurately.

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.