My first experience with a 12th car was on an open tarmac track with 2s boosted and a 9.5T that was insane. Faster even than 1s boosted 4.5T.
2s boosted on a 12th car is insane and a nonsense for the 99% of the drivers.

On redrc they have publish a note regarding changes on 12th for the worlds but they do no't say anything regarding 2s, hope it got stopped at any moment.

Cheers