iTunes is one of the best applications Apple has produced. However, once the song database increases, it becomes very difficult to organize the songs it contains. Some songs are present in multiple groups. Though we can manually create the groups and maintain them, its a very cumbersome process. Also, there is no formal method for having the same song in multiple groups (or genres). One possible option is to use "Comma Seperated" genres. However, using this method, it is not possible to "add" a genre to a bunch of songs while keeping the existing genres intact using present options.
I've created a couple of scripts to work around this limitation using Groups. Instead of Genre, the script allows us to add/remove group to the "Grouping" field in the song, which is mainly unused. As an example, a song may fall into Remix, Dance and HipHop categories. We can manually create playlists for all the three and add the song to that. However, if we wish to create a new playlist, which contains all the songs of Dance and HipHop categories, then it's not easy to do manually. It becomes more complicated when we add a new song to Dance category, we have to remember to update our new playlist also.
To achieve this result, however, you can use this script to "Add" a group to the selected song(s). Once proper groups have been added, "Smart Playlists" can be generated that contain these categories. Also, a single group can also be removed from the selected songs without modifying other groups.
[robg adds: I downloaded and tested the scripts; they work as described here. I don't do much with grouping music using Genres (Smart Playlist -> Not Recently Played is my usual mode of listening), but if you do, this unused field and these scripts could come in handy.]
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