I have an incredibly productive staff developer. Not only does he work a lot, he also produces, and it's very high quality. He also does a relatively poor job of upskilling his teammates, and is a little rough when mentoring. This is not intentional (i.e. he's not a jerk).

Overall I don't know if, in the context of a staff developer, he's vastly more productive than say, another dev I have who produces less but levels-up his team better than almost anybody I've ever seen.