[jiayo]

When US (NTSC) shows are aired in Europe (PAL), the framerate difference necessitates a small speed-up. It's barely noticeable, except when music is playing, at which point it is very, very noticeable. Yes, it's a little higher pitched, but it just feels wrong and is immediately noticeable. I think it's about 3% speed up, which is exactly what's being described here.

[bitnasty]

NTSC is 29.97 fps and PAL is 25. That’s almost 20%!

[sgarland]

They may have been referring to film (24 FPS) or its broadcast equivalent (23.976 FPS) being shifted to PAL, which is quite a bit smaller of a jump.

NTSC —> PAL can either be annoying, or difficult to manage without artifacts. If the NTSC source is telecined from a 23.976 source, you can invert that process to get the original back, and then deal with the minor time shift to PAL. If it’s pure NTSC, there’s a lot of filtering to be done to get an acceptable result. At least, last I played with it.