Math doesn't "govern" pivot systems - it describes idealized versions of them, as it can with any aiming method.
pj
chgo
If the pivot is well-defined and consistent, like a "half tip offset" from center cb, and there's a known reference line through center cb from which the offset pivot is applied, then math can certainly predict where the ob will go for any given shot.
But anytime we attribute an effect (result) to some unknown cause (reason for result), we ignore logic and render math useless.