I had no idea what MDP was, but after a quick search I assume it refers to Music Player Daemon, for anyone else wondering.

Euphonica tries to make minimal and sensible assumptions about your library's folder structure.

Tracks from different releases (albums) should not be put in the same folder. Preferably, all tracks of the same release should be put in the same folder.

How hard is it to stop making this assumption? Why is almost every music player adamant on making it?

Not every song belongs to an album, songs released together might belong to different albums and not every album is released at once. Not to mention folders can serve any kind of organization need other than grouping songs of an album.