ob2s wrote:
I will take the risk over appearing to be a braking riding mother f*cker.
Then don't use B Mode. I find it mostly useless and if anything an impairment to efficiency. The e-Golf is not a great example of a "one foot EV" like a Tesla.
D1, D2, and D3 modes can be useful and do not turn on brake lights, but even then I only use those modes when descending long grades.
As far as downshifting, a Porsche mechanic friend (who also raced Porsches at the time) told me back in the 1980s that brakes are a lot cheaper to replace than clutches and driveline parts. That advice changed my driving style forever. Downshifting is great for holding speed down long grades (as are D1-3 on the e-Golf) without cooking brakes, but not so good to setup entry speed into a corner, especially in a track environment. Being in the correct gear at the apex and tail out is important, of course, but that is to accelerate out of the turn, not slow down on entry.
To answer your question, the connection between B Mode and the brake light is in software. You would need to be very good at coding to figure that mod out.