musical douche 

any person who typically writes overly complicated rhythms and parts that sound generally unappealing, with varying levels of success.

Mason Bates is a musical douche.

musical douche by Dwizzle69 February 19, 2015

Musical douchery 

when the composer or writer of a song puts in a part of a song that makes no sense as to why it would be there and so the only explanation is that it is there simply to screw with the musicians and/or audience

Musician #1 "Why do we go back to minor for three bars? It's completely pointless"
Musician #2 "No idea, must just be some musical douchery"

Musical douchery by Nooche13 February 26, 2011