timing settings are slightly more than just a bunch of rulers to snap notes to; they need to match the song's
time signature for proper kiai and menu cookie pulsation, nightcore mod audio samples, and to reflect the song's nature in the closest way possible.
a negative offset means that an audio is cut (or composed) in such way that the first downbeat doesn't exist:
this way, everything before the first real downbeat counts as
anacrusis (thanks to
Shiro for sharing her knowledge of music theory).