Putting aside the issue of the actual current flow in the neutral wire, if the current is 1.44 amps with the 'Economiser' fitted, in comparison to 0.833 amps without it, does that mean it actually costs more to run and yet gives out less light? This is very confusing, because I know if I were foolish enough to fit an 'Economiser' unit to an Edison Screw type bulb here, on an EU 230v 50hz single phase supply, the effect described would not occur.
