Kurenai

Well since this attack as the ability of landing a critical outside of Hide. It seems that the Criticals are Stacking basicly, Your getting one critical for being in hide and another critical due to the ability of the attack. Having the chance to critical even without hide. So it may be a bug with something not registering and leting the system know your in Hide remove the % chance for the out of Hide Critical. However, it would be nice if it wasnt.

Tried to explain it best I could. =)

Kurenai