Have you read the Core Rulebook?

[DigitalMage]

No, and I don't intend to as it'd not worth the effort to me. It is the first RPG I have run where I haven't read the core book cover to cover (although just reading the 3.5 Monster Manual now; phb and dmg read cover to cover ages ago).

[Lex Starwalker]

I have read the entire thing at least once, and I've read many of the sections numerous times. Desptite that, almost any time I reread a section, I pick up something new that didn't stick the past times I read it.

When playing Pathfinder, it's painfully obvious who has read the CRB and who just uses the SRD or Paizo core rules online. I guess you just get a better "big picture" understanding by reading the book as opposed to reading the rules scattershot online. I suppose you could get the same effect by reading the Paizo rules online in their entirety, but most people I know who use them jump around.

[Calybos1]

Yes, I've read it all... but at various times and multiple sittings, in different order. Going straight through would've been exhausting and counterproductive, since different parts are more urgent/important than others.

[Ciaran Barnes]

Every few weeks my group uncovers something that has changed since 3.5. I suppose that could justify a reading of the book, but on the other hand none of the differences has been game-breaking.

[Rickmeister]

YES!
And I try to read up on the forums as much as possible, because I feel it's my task as a DM to be on top of the rules.

[Rickmeister]

Oh, and that's why I only allow the books I have/have read, unless there is a REALLY good explanation/flavour behind it.

MY group has been playing Kingmaker for several (4) years, and I'm still 95% certain every time there is a discussion.

[Rafim]

Sure!! it's the base for playing..as a dm i read it all and all the spells too cause i'm a wizard in another group :)

I see a lot of guys that dont read the book.. that's why a lot of questions come out :) (my players sometimes jump up some parts (bad thing if you want to learn the game). U can learn things by playing but it's boring when u are at table and u dont know what kind of actions you have in a round.
Beside Race Classes and Feats you MUST read the ability chapter and read almost your class abilities and can you do with those.
The Combat Chapter is the base of the game
If you are a caster you must read the magic chapter too before your spells
Everything you skip is something that will slow the game, the combat, the exploration and whatever you will do.. and the GM or a more experienced player will be obliged to teach that to you..

The best thing that most of the player dont think about is that if you know the rules you know your options in the game. Knowledge is power