Giants arent going to play all out this week. Their focus now is preparing for the playoffs. All any NFL front office and coaching squad cares about in this scenario is preparing for the playoff game. Divisional rivalries, roughing up the Eagles etc does not have the same meaning to pros as it does to fans.
Momentum is also an artificial construct in this scenrio. Giants got their momentum in their blow out of the Colts. Mentality now will be "lets bring that intensity to the Vikings............ we have this meaningless scrimmage thing that doesnt matter next Sunday which many of you wont play in..."