Goutor doesn't specifically cover the process, but ostensibly after one has categorized content notes, they are filed together in one's box under that heading. (p34) As a result, there is no specific indexing or cross-indexing of cards or ideas which might be filed under multiple headings. In fact, he doesn't approach the idea of filing under multiple headings at all, while authors like Heyde (1931) obsess over it. Goutor's method also presumes that the creation of some of the subject headings is to be done in the planning stages of the project, though in practice some may arise as one works. This process is more similar to that seen in Robert Greene's commonplacing method using index cards.

What's the difference between a problem (addiction) and a hobby? Where does obsession fit in?