[Yoda]

The "clubface LAG", the torque of (or resistance to) the rotation of the forearms (or clubface), along with the other three: pivot, auccumulators and club.

In his recorded GSEM classes, Homer Kelley never referenced Clubface Lag, so we have no "official" authority as to its existence or non-existence.

Personally, I would classify the phenomenon you describe as Accumulator Lag. Specifically, the effort of the #3 Accumulator (Left Hand / Clubshaft Angle) to maintain its In Line condition (Left Arm and Club / Rhythm) during the rotational Overtaking process, i.e., the Overtaking of the Hands by the Clubhead during the Release Interval (Release to Follow-Through).