[Archon_Wing]

Nanoha basically took advantage of the situation. Time was on her side; Fate's situation's pretty hopeless-- even if she wins against Nanoha there's nothing to stop the TSAB from going in and arresting her. Fate was fighting on desperation and could only aim for taking out Nanoha quickly as possible. Add to her recent flashbacks, and Nanoha easily has the mental advantage

For this reason, Nanoha had no need to compete with Fate with beamspam or getting the upper hand. It would just leave her vulnerable (though sadly, they left out a fight that had that in the series) ; as long as she plugged any holes in her defense she was in good shape. Look how little she fires compared to Fate in the last fight at the start. Basically it was already over once she tanked Fate's super move. Unlike Fate, who resorted to the big guns right away, Nanoha wore her down with a weaker divine buster and then took out her trump card out.

Not exactly a genius thing, but Nanoha did outplay Fate completely.