This is an interesting discussion. But the logic discussed above often implies a somewhat different hierarchical structure, e.g., documents nested under another document.
As louise noted in another thread, links are interesting because they have direction.
Think of the “Welcome” page in the Tutorial Database. It is a document, not a group. Yet it subsumes (a bit like a group) all the other documents in that database, using links. The possible flows of links are complex and non-linear, and are often bidirectional. So this is not a simple hierarchical structure, but it is a structure. That structure allows DT Pro to publish the Tutorial Database as a Web site simply by bringing up the Welcome page and clicking on File > Export > as Website.
sjk, I know I’ve said this before, but I often use a “Table of Contents” note that serves to “pull together” a set of other documents, whether they are in the same group or not. Sometimes this note has an explicit hierarchical structure, as when I create a list with sub-elements as an outline of an article or project I’m developing, and link the list elements to other documents that “flesh out” each of the list elements. I might choose to make some of the links bidirectional, as when I add “TOC” links back to the original note in those linked list element documents. Or I may add other links to still other documents, such as a list of reference sources in one or more of my “section” documents.
Yes, I’ll file that “TOC” note in a group for my article or project, but I’ve created a note that refers to one or more other notes and provides a great deal of logical power for establishing relationships between documents. Although this can be done with Wiki linking, I usually prefer to select a text string, do a Control-Click and select the Link to contextual menu option. This static link approach prevents possible confusion that might result from the Wiki link approach.
I’m initially limited to using a rich text document to establish these relationships. But my final product could be an external (to the database) Web site, MS Word or PDF document(s) that maintains the structure and cross-linking I’ve established. (Pages 2.x allows me to copy/paste my rich text to Pages and export to Word or PDF with all links working.) So, with a little tinkering, I can transfer an article or project developed in DT Pro as a very well laid out and formatted final product. I can make that final product linear (e.g., a printed article) or non-linear, as desired.
I’m sure that we will see additional and powerful new features for “collecting” documents through other relationships than group or link organization, in future versions of DT Pro. Just wanted to emphasize once more the potential of using links in a note as an alternative to a hierarchical group structure for relating documents.