It was never put in the manual until the Rapida...dont ask me why it was omitted

but it is in most of the speed controls out there.
ENSA controls how much power get sent back to your battery during the run 100, 70 or 30%. 100% is the default setting. NEVER run a Schottky diode with the ENSA at 100%...you will burn out high speed fets.
If you run 70% or 30% you must run a Schottky diode.