Beemers were using interesting engine management. They dropped cylinder(s) in the middle of slow corners to make it 2 or 3 cyl engine for long periods (not just milliseconds) for better traction management. Once out of it all 4 cylinders chime in and off they go normally. Interesting take on traction control.
With this they can have a 2 cyl 500cc or 3 cyl 750cc for those slow sections that is much easier to manage than full blown 1000cc engine with traction control cutting in.
Okay, I will be arrest.