Therefore, can I get away with it if "In use", I only engaged the 15.5mph limited throttle after I started pedalling, and disengaged the throttle shortly before ceasing pedalling? It's illegal according to the letter of the law, but might not be in it's "Spirit". But I'll leave my throttle disconnected for now, despite all the agony from my damaged and aged knees while starting at lights, or after a sudden stop at high gear, or on very steep hills etc.All these more complex arguments will come to nought once a case is referred to a senior court such as the high court, appeal court or supreme court. There one or more senior judges, often with the assistance and advice of a master at the high court, will decide what the spirit of the law is. i.e. What parliament intended.
That can only have one outcome since the spirit of the law is contained within its title:
Electric Assist Pedal Cycles
i.e. The electrical element is only there to help the rider propel the bicycle, so merely spinning the pedals does not constitute the rider propelling the bicycle with the motor assisting.