Not sure if this helps, but try this adaptation of Saq's RenameTag
bookmarklet*:
http://tinyurl.com/36uqms
(http://xdexavier.googlepages.com/sharebookmarklet.html?author=FND&description=Renames%20all%20occurrences%20of%20a%20tag%2C%20allowing%20to%20replace%20a%20single%20tag%20with%20multiple%20tags.&title=RenameTags&code=(%0A%09function()%20%7B%0A%09%09if(window.version%20%26%26%20window.version.title%20%3D%3D%20'TiddlyWiki')%20%7B%0A%09%09%09var%20oldTag%20%3D%20prompt('Enter%20the%20tag%20to%20rename'%2C%20'oldTag')%3B%0A%09%09%09var%20newTags%20%3D%20prompt('Rename%20tag%20'%2BoldTag%2B'%20to%3A'%2C'newTag')%3B%0A%09%09%09newTags%20%3D%20newTags.readBracketedList()%3B%0A%09%09%09var%20t%20%3D%20store.getTaggedTiddlers(oldTag)%3B%0A%09%09%09store.suspendNotifications()%3B%0A%09%09%09var%20j%3B%0A%09%09%09for(var%20i%20%3D%200%3B%20i%20%3C%20t.length%3B%20i%2B%2B)%20%7B%0A%09%09%09%09t%5Bi%5D.tags.remove(oldTag)%3B%0A%09%09%09%09for(j%20%3D%200%3B%20j%20%3C%20newTags.length%3B%20j%2B%2B)%20%7B%0A%09%09%09%09%09t%5Bi%5D.tags.pushUnique(newTags%5Bj%5D)%3B%0A%09%09%09%09%7D%0A%09
%09%09%7D%0A%09%09%09store.resumeNotifications()%3B%0A%09%09%09refreshDisplay()%3B%0A%09%09%7D%0A%09%7D%0A)())
This allows you to replace a single tag with multiple tags (e.g. "foo"
turns into "bar [[lorem ipsum]]"). (Just to be on the safe side, make
sure you create a backup before applying this.)
However, as I understand it, you do not want to assign all subsets to
each tiddler tagged with "projects" - so we'd need to specify some sort
of condition for automatic processing...
> Therefore, what I would require is just to be able to manage all tags of
> all tiddlers in one single place.
Have you tried Eric's TiddlerTweakerPlugin:
http://tiddlytools.com/#TiddlerTweakerPlugin
HTH.
-- F.
Not sure if this helps, but try this adaptation of Saq's RenameTag
> Suppose I have 100+ tiddlers, tagged "Projects".
> Now I have changed my mind, and I'd like to divide them into tags
> "Project1", "Project2", "Project3", creating three subsets.
bookmarklet*:
http://tinyurl.com/36uqms