This is correct. The reason is more or less that humans are really, really good at staying in sync, but, even with only 2 parts to listen to, it starts to get

This is correct. The reason is more or less that humans are really, really good at staying in sync, but, even with only 2 parts to listen to, it starts to get almost impossible levels of effort to keep proper time. In person, without any network lag, musicians can make adjustments in real time (e.g. always, always, always follow the soloist, even if the soloist is off tempo or off pitch). The conductor is listening to the soloist, too, so you don't need to worry about conflicting directions. Here are a couple of examples I know of on YouTube where a single musician plays multiple parts, which are then edited together: Now professional cellist, graduating senior at time of recording, Sarah Chaffee playing an original transcription of Alice Cooper's Poison with 5 cello parts (with a short guest appearance by Shostakovich at about 2:42, then showing up again in the outro to play us out at 3:33): https://www.youtube.com/watch?v=PjYwQHFsld0 https://www.youtube.com/watch?v=PjYwQHFsld0 Professional cellist Wells Cunningham playing the Handel- Halvorsen Passacaglia: https://www.youtube.com/watch?v=NseBdxfHk5k https://www.youtube.com/watch?v=NseBdxfHk5k This guy has a really, uhm, interesting violin technique. ;) Just for the fact that he chose to play the instrument the way he did tells me he does not actually know how to play violin. What he's doing is playing it like a teeny tiny cello. Since the notes are so much closer together on the respective fingerboards on a violin than on the cello, I'm betting he needed an extra take or 2 on that. His performance is passable, but nothing when put up against the performance of an actual, professional violinist.