Might have been the TCS pulling back power because it seemed like it cleared up in 4th gear and on. Definitely was breaking up though. They should stick with 1/2 mile racing, they're going to break less stuff, screw 1/4 mile drag racing.
1320 just dropped the video about it to today. The 252 pass was a rolling start and the 255 was from a launch. I don't think there was too much of a change in power though.
It wasn't a rollilng start, it was them just not leaving hard. Their launch settings were set to the drag strip so it was too much, that's why they lowered it the next day and used it. He said the turbos weren't spooling until the top of 3rd gear without the launch.