airbubba - "It advocated the aggressive use of rudder in upset recovery. " The videos are available on the 'net. In them Vandenburgh doesn't advocate aggressive use of the rudder.
Children of the Magenta Line -
https://vimeo.com/159496346
Rudder discussion - 15:30 (ends at 16:10). More discussion at 29:00 about using rudder at 90 degrees while the nose is below the horizon.