Also noticed something interesting on the launch data from this weekend. Comparing the HP vs time data to the RPM vs time data, it appears to me the optimum time to do the 2-3 shift is ~ 4300rpm, which is before the car shifts itself (hp is droping fast at the 3.1 sec point but the shift doesn't happen until ~3.6 sec). Also note how much less peak hp is applied to the ground in 2nd than 3rd (more drivetrain loss due to fluid coupling of the TC, and then it locks up in 3rd, might be less boost in 2nd also, haven't looked at that).
The driver was letting up on the skinny pedal at ~4400 rpm at the end of the 3rd gear range which is why the HP is falling off at time ~6.4 sec. However, it might also prove beneficial to do the 3-4 shift a little earlier as well...
2011 335d 11.8 sec 120 mph 1/4 mile NHRA certified track
2004 Ram Cummins with lots-o-mods