I'm not talking about the PDK history. I'm talking about the current race cars, For example the 991 cup cars run sequential gearboxes (either paddle and clutch or lever with clutch).

 

I once had the pleasure of lunch with Derek Bell. I raised the subject of the PDK concept and asked his thoughts on it. Note this was years before it became a production transmission. Derek replied that it performed sensationally on the track, but the drivers didn't want to use. It added a lot of weight to a 956 in 1983, and the drivers thought that it didn't surpass their own skills. He said the latter may be down to, "I'm a skilled factory Porsche racing driver, and don't want something that masks my own skill". At the time, the development units used in the 956 and later 962 weren't all that reliable. There were still a lot of bugs to be worked out. Mind you this was 30 years ago.