Geas

Might be a completely silly question but...
Do the song masteries still rise if you are not part of the guild?
Atleast one might assume they would but having no way of checking them leaves me clueless.

As far as I know the song skills might improve if used, and degrade
if you don't. The second part is an impression I got after not using
certain songs for ages, and I recently noticed an improve for a song.