[CanAutM3]

A small related anecdote:

At my last track event, my car suffered from “chassis restricted function” error due to a faulty strut accelerometer. When the fault appeared after one or two laps, the EDC would default in full stiff and the engine in Efficient. DSC could still be switched off (although MDM was unavailable) and the DCT could be put in S3, so I kept driving it for the remainder of the two day event despite the limited EDC and engine functions.

I can now without any doubt say that Efficient is significantly damped and non-linear and completely sucks for track use. At high RPM, the power can only be found in the last quarter inch of pedal travel and there is significant lag with the delivery of power, which makes it quite unpredictable.