John,
I don't know. The trace I have shows a sharp right rudder application, followed by modulating right rudder use. From experience I do know that too much nosewheel deflection can cause tramping and loss of NWS effectiveness depending on surfae conditions (probably not a factor on a dry r/w), but the rudder is a much more effective aerodynamic control on the ground above about 50kts than any other conventional type I have flown, but as to why full scale deflection wasn't used - I cannot guess.
I cannot think why full rudder would not be appropriate (the aeroplane had the distinct advantage of having virtually no yaw->roll couple).