"Close the Door Behind You" is a cyclical practice strategy. This method described is not a technique but rather an overall approach - a strategy. The strategy organises our practicing into three clearly different 'rooms', with each its own focus, purpose and mindset. The three rooms are: The Laboratory, The Gym and The Concert Hall.
This book describes the three very different approaches to practicing, and it argues that we should only enter the next room of practicing, when we can safely close the door behind us to the previous room. If we follow this strategy, we will achieve a much more efficient and personal workflow.
When we have passed all three rooms, completed the turn, a new circular movement begins - but obviously from a more advanced starting point, just as when we ascend a spiral staircase.
On top of this the book suggests a lot of concrete tips and tricks for practicing in all the three rooms. It also suggests original ways in general of understanding the world of classical musicians.
Morten Zeuthen's background for writing the book Close the Door Behind You is a long career, both as an international performer as cello-soloist, as chamber musician, and as a solo cellist in the leading Danish symphony orchestras. However, the ideas he describes owe more to his status as a central figure in Danish cello teaching - as the professional success of his students surely attests.