Sam Vimes could parallel process. Most husbands can. They learn to follow their own line of thought while at the same time listening to what their wives say. And the listening is important, because at any time they could be challenged and must be ready to quote the last sentence in full. A vital additional skill is being able to scan the dialogue for telltale phrases such as "and they can deliver it tomorrow" or "so I've invited them for dinner?" or "they can do it in blue, really quite cheaply.
Terry PratchettThis time it had been magic. And it didn't stop being magic just because you found out how it was done.
Terry PratchettAnd what do you really do? asked Tiffany. The thin witch hesitatied for a moment, and then: We look to ... the edges, said Mistress Weatherwax. There's a lot of edges, more than people know. Between life and death, this world and the next, night and day, right and wrong ... an' they need watchin'. We watch 'em, we guard the sum of things. And we never ask for any reward. That's important.
Terry Pratchett