Thank you for your response, Jim.
I don’t see how this TagPacker is doing anything particularly different than just using hierarchical tags. And it’s not similar in function to the Tags filter pane.
By selecting a tag in the filter in TagPacker, the results shown are filtered by that tag, and the tags available to select in the filter, across all the tag packs (groups of tags) becomes smaller so that it only includes tags from the subset of results being presented in the main pane.
When multiple tags are selected, we get the result of combining them using “AND”.
That is exactly the behaviour that I see in DEVONthink’s Tags Filter pane.
The difference is that TagPacker groups them.
Or did I misunderstand your comment?