Between Fable 2 and Fable 3, the co-op is a cool little feature no doubt. Here's the thing. When you come into someone's game, they may have never played before. They might have played a hundred times and forgotten. It's understandable to need help with things in Fable 3, everyone did at one point or another. I suppose my point is that we should treat one another like we would like to be treated. If someone has the achievement for the books, but don't remember because it's been forever ago since they did it, this doesn't mean they won't try to help you. Also doesn't mean that they should be insulted. Thanks. Sorry if this is in the wrong place.

TL;DR: Treat others in co-op as you would like to be treated.