I've noticed something that Neil Gaiman would occasionally do when writing. He would go: He sat down, picked up a pencil. Instead of: He sat down and picked up a pencil. Is that grammatically incorrect? Whether it's fine or not, it does throw me off a little bit. Still, I enjoy his books a lot. Thanks. I just wanted to hear your thoughts.
Neil tends to write as if he was telling things orally. It's his literary voice, which is a good thing to have. Whether it's gramatically correct I can't say, but if it's not I'm sure it's on purpose.
In fiction, once you have mastered the technical rules of grammer, it is perfectly okay to break them every once in a while as long as it serves a purpose.
It's a comma splice, a variety of run-on sentence, but Gaiman is a good enough writer to get away with it.
Yes, as others have mentioned, that is a written artifact of the oral tradition. One of my current favorites, M. John Harrison has an unusual tendency to start a chapter or split the action of a chapter with a little thing like: What happened later that day was this: or These are the things Penelope was thinking: And then he starts a new paragraph and tells what he's going to tell.
Exactly. Also, fortunately for him he has a rich, interesting voice, and so he narrates his audio books.