Not sure if this works for you but how about creating "fake albums" for your playlist tracks ?
If you are ok with your music tracks played gapless, you could play around with this maybe ...
- create separate library (you could do a restore from a backup). Go to manage fields
Make sure all tags are NOT set to write tag to file in Options=>Library Folders
- Options audio=>Track Change set gapless for sequential tracks; set transitions for the rest as you wish
- Import your programming playlists to new library
then select all tracks from each playlist individually and retag with one name (like Playlist Album 1, 2, 3 etc) and change the Album artist to Various or Multiple Artists (why you do not want the metadata change written to your files permanently
(note: you might also have to select tracks of fake album and go library tools=>fill track numbers from list order.)
e.g. -- 1 "jingle" every twenty minutes . Each "fake" compilation album of approximately 20 minutes in length. For three hour program you would need about 9 "albums" ... any non sequential transition would have a transition or a gap (the jingles), all "albums" would be played back gapless which sounds pretty good using the volume DSP options - unless you go from grunge to opera I suppose^^
Regardless backup your stuff before you try !! You could also import a copy of the actual files into the secondary library in a different place on your hard drive to be less risky