Form VII is considered to be a very dangerous yet powerful form. Known primarily as Juyo, it feeds on one's own emotions to guide its blades. As such, it is strongly associated with the dark side and the Sith, a form forbidden by the Jedi to members of its own order.
Mace Windu, however, created a variant, Vaapad, that feeds on the emotions of one's opponents rather than that of the self. This supposedly allows one to use this aggressive and powerful form without using the dark side, although a Vaapad practitioner still skirts close to the dark side nonetheless and needs to be strong enough to resist it at all times.
At first glance, Mace's Vaapad seems to be the perfect counter to Sidious' Juyo. However, the full power of the dark side within Sidious, revealed in all its terrible glory, is unprecedented for any living Jedi, overwhelming all but the greatest masters (like Yoda).
Due to the nature of Vaapad and the circumstances of events that happened in the Supreme Chancellor's office, is there any chance that Mace, master though he may be, has subconsciously succumbed to Sidious' overpowering darkness, possibly influencing his decision to kill Sidious there and then rather than arrest him for trial before the Senate?
