Come to think of it that function of Commander is pretty cool if you wanted to customize playlists for various dates in the game, I think you could just put the tracks you want to play all the time in the game's Gram folder and then put additional ones in the Gram folders in Commander and it would insert them in the game for the specified date.
You'd just have to be careful with the filenames in both programs, I guess, to make sure you didn't run into the kind of conflict I was apparently having. But it is a neat idea to have date-specific radio broadcasts or even music tracks available for certain important historical dates.
Yikes I just had a mental image of me diligently researching the release date of every single track in my collection to see when it should, in theory, become available to be played as a record on a u-boat, and proceeding accordingly. Knowing me, I will do this at some point.
My goodness the awesomeness of this game and the things people have done to it and what can be done to it to make it even more awesome...