So far, only the Arkenhammer is known to allow Rocking Out.
Stanley's claims may be exaggerations. Book 1 featured one fight between Stanley (Rocking Out) vs. mostly Transylvito units using show tunes. Stanley's side suffered many losses and had to retreat from the hex under the cover of Foolamancy. While this incident does not prove that Dance Fighting is superior to Rocking Out, it does demonstrate that Rocking Out forces are still vulnerable to "less Titanic" but numerically superior opponents.
Real World References
Rock music is a real world genre of music that, in its most basic form, heavily features guitars and a strong back-beat from a rhythm section consisting of a bass guitar, drums and/or piano, organ or keyboard.