I rode the GS through all weathers in London without ASC. You've got to be really ham fisted to get the thing to spin up, even when greasy. But there's no harm in having a bit of electronics to help...........as long as it doesn't go wrong
Another marketing gimmick to differentiate BMW products from the others out there - which is fair enough, but in practice it's all a bit unecessary really; just like those Servo ABS brakes that were dropped once they became a liability.
It strikes me as a 'solution looking for a problem' - good on BMW for trying though - because 'mad' ideas sometimes lead to real progress.