This may also apply to Knightriders thread.
I tested a one year old soft start Date Code 08A01 and a few year old before soft start Date Code sticker fell off Lamp Modules.
Using a 40 watt incandescent bulb.
At the full on state. Both had between 3.5 and 4.0 volts difference on the wall outlet and the modules outlet.
At minimum dim the soft start went to a 20 volts on the modules outlet.
At minimum dim the older one was at 1.95 volts on the outlet.
When off the older ones local sensing had about 0.040 AC volts and 0.0045 DC volts on the modules outlet. There is a diode in the older ones.
When off the soft start one had 0.010 AC volts on the modules outlet.
So I would say if you can't get almost 100% brightness when ON. Either there is a problem with a run of the modules or X10 again has changed things.