Chess seems like an odd addition there, would two people who are able to discuss strategy and reason about the next move be worse than one? For writing, workshopping jokes or scenes happens a lot doesn't it? Particularly with scripts.

When it comes to novels and art though, there's a focus on producing one persons imagined work, edited and helped by others. When it comes to programming, particularly in a company, there's a problem to solve.

Is it common in other fields of engineering to say that only one engineer can work on a problem at once?

> Individuals do these things all the time.

Individuals code alone all the time too. What I'm commenting on is the idea that programming together with someone is terrible.

Do engineers pair CAD on e.g. bridges? Does anyone know?

> Novel writing is complex, chess is complex, art is complex.

Well one thing you need to consider is that most software is not written in small, artisian batches but at scale. Pairing is one way to promote doing development and all the things you mention at a greater capacity than the individual.

Maybe? Dividing up the work is the other, traditional, way to work at scale. It hasn't been shown that pair programming is more effective.