Oh, so the NTSC masters have slowed down everything, including Carlin’s narration? That’s real convenient.
You do know that it’s possible to edit the speed of Carlin’s narration without it affecting the pitch at all right?
There’s no need. Nothing was ever slowed down or sped up – Thomas was shot/edited/recorded in sync to 25fps standard in the U.K.
When brought to the US, all they did to the footage was apply pulldown. It wasn’t until 2012 that they started converting the series to 24fps (CGI era only).