I agree that the place to do this is in the tiddler for the tag (the tag’s “home” tiddler).
But I think tagging is not the right name for the field!
That’s because tagging[] is already a filter operator, and the solution here would explicitly involve NOT literally tagging (or untagging) the tiddler in question, but simulating some behavior that is ordinarily associated with having (or not having) a tag.
Overriding behavior associated with $:/tags/ViewTemplate — while not removing the tag — is the clearest use-case, so that’s the need I’ve developed a proof-of-concept for.
The rest of this post distracts from this thread, so I'll tuck it into details
I’m not thrilled with my fieldname choice, but I tentatively chose override-out as the fieldname, such that if $:/tags/ViewTemplate (the tiddler for the tag) has something listed in its override-out field, then the wiki is designed to treat it as excluded from the normal effects of that tag except:
- it still actually has the $:/tags/ViewTemplate tag, BUT the tiddlers tag-wrapper (in view mode) shows that tag as overridden.
- It still appears in the tag’s dropdown, BUT with
next to it in tagpill
I welcome feedback!
Here’s a screenshot of current state. Note that the tiddler is not showing its subtitle. But in fact the subtitle viewtemplate is still tagged as viewtemplate at its own end. But under the tag tiddler, it’s listed in that override-out field:
Here’s the separate thread on “disregarding” tag-children from the tag-home end of the relation: Tag ($:/tags/ViewTemplate) allowed to "disregard" some tag-children

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