'initialising' is the procedure to set up the twin plate clutch, I don't think you can get the car in gear if that is not done. If the clutch pedal didn't have quite enough play, when the fluid in the system expands, there is not enough 'slack' and will be like the driver is pushing the clutch pedal slightly. My total guess is that may be the case here, normal driving would appear ok but at higher revs it cannot cope.