I mean that its an easy way to 'start' a secondary theme. On linux;
cd ~/mystic/themes
cp -r themes/ new_theme/
Yep! As long as you plan to modify every part of the theme :P
The reason I think it might make sense to not do this, even though it works 100% and is a great foundation to begin on, is any change you want to make in your default theme then won't be reflected in the new theme unless you go change it there as well.
Either way works, though!
--- Mystic BBS v1.12 A49 2023/02/26 (Linux/64)
* Origin: m O N T E R E Y b B S . c O M (21:4/173)