garygid wrote:I think, for better Safety, the EV should turn ON
the brake light at ANY Regen level.
That would mean brake lights on the whole way down a hill. Doesn't having brake lights on all the time lose the startle factor that warns the following driver of a speed decrease?
Using mild regen going down a hill is similar to descending a hill in a lower gear in an ICE car, the usual technique used by any competent driver on hills. (The rule-of-thumb is that one descends the hill in the same gear as is used to climb the same grade.) As it happens, the Eco regen slows the LEAF quite a bit less than third gear on my ICE cars; I wish it could be dialed up a bit so I can reduce my speed going down those grades without having to use brakes.
Descending a grade in a lower gear or using regen doesn't involve slowing if the grade is relatively constant, so there is no need to warn following drivers with brake lights. It is only the sudden change in speed that needs brake lights, IMHO.