Well, Harmony of Dissonance takes place in the time period of Baroque art and music and the they tried to emulate that. They definitely got the art down, but trying to capture the Dissonance technique from Baroque music with a messy 8-bit sound font just isn't happening:
https://www.youtube.com/watch?v=ieZqkB3v7tI
Dissonance is the purposeful lack of harmony. It's used to give the impression of instability, anguish, and a need for resolution to stability. In the song I posted, you can hear the two musical patterns exist apart from each other, and the overlapping and battle of the two creates the emotional weight of the piece. If you go back to Hod's soundtrack you can understand what they were going for much better.
'Harmony of Dissonance' is a play on this notion, as the seemingly two different castles aren't meant to be separate like in SotN, but two entities that overlap each other. I guess it also loosely references cognitive dissonance with Maxim's limited character development.