Foot feint balk?

[Paul L]

R1, left-handed pitcher in set position. As F1 raises his free (right) foot, and without making any movement towards home, his free foot is drifting towards first base, but not beyond the 45 degee line. As he starts his kick, F1 moves his free foot toward first as if he is starting a step and throw to first (past the 45 degree line, more towards first than home), but without moving his throwing arm or upper body toward first. Then as he gets to the top of the kick, and in one continuous motion, he steps toward home and delivers the pitch, landing his free foot more towards home than first. FWIW, F1 does not do this without a runner at first.

OBR 8.05(b) says it's a balk if the pitcher "feints a throw to first base and fails to complete the throw".

So, does this kick towards first constitute an illegal feint?