In the Battle of Princeton, why wasn't gallantry enough for British victory?

Gallantry was not enough for the British because
Washington proved to be a fairly resourceful commander of the Colonial troops.  Dividing
his troops in half in order to flank the British so that they would essentially run into
Colonial gunfire proved to be a tactic that was successful throughout the Revolution. 
The Colonial manner of fighting that consisted of smaller and more agile mobile units
against the large and sometimes clunkier British forces was a tactic that Greene used in
the South and Washington used at Princeton.  When the British are in flight mode,
Washington says, "It's a fine fox chase."  This reflects the sheer strength of the
Colonists.  British gallantry and adherence to pomp and circumstance was no match for a
different technique of fighting.  In the end, this is what ends up becoming critically
decisive for the Colonists in their victory over the British.  The British method of
fighting, of which gallantry was a significant ornament, is not one that assisted the
British in this circumstance of combat.