Say I have sources set up as follows:
HTPC -> \\server\HTPC
Anime -> \\server\HTPC\Anime
Anime - Current -> \\server\HTPC\Anime\~Current
TV -> \\server\HTPC\TV
As you can see, I have a source through which I can access everything, and other sources which are essentially shortcuts. If I mark a show as watched in e.g. "Anime", it will be appropriate marked in the other sources (since the marking is against the path).
However, in the case of "Anime - Current" above, it contains links (actually junctions, hosted on Windows) to the shows that are currently being shown. As shows finish or start I add and remove junctions in the \\server\HTPC\Anime\~Current directory.
What I'd like to be able to do is say something like "Anime - Current" is equivalent to "Anime". Then, whenever a path is marked (e.g. watched/unwatched) in either "Anime" or "Anime - Current", the corresponding path would be marked in the other source. Missing paths would not cause errors, but would be recorded.
I don't think I could achieve what I want using smart playlists (though I'm not an expert) and in any case I've found libraries don't work for how I want to use my HTPC.
In a similar vein, I'm likely to want to create a multi-path source soon - something like:
Anime -> \\server\HTPC\Anime, \\server\HTPC\Anime - archived
where the two directories are on different drives (\\server\HTPC is a directory of junctions to multiple drives). I'd like it if I marked a path as watched in either of the directories, it would be marked for both. This would give the flexibility to archive things (move them to the other drive) and keep the watched status - essentially saying that "\\server\HTPC\Anime" is equivalent to "\\server\HTPC\Anime - archived".