Yes, was just an off the cuff remark, not completely accurate.
The book does take the time to provide alternates at many points. It should explain "what really happens," but it first does that for waterfall, then spiral, and agile, etc. If you are reading the waterfall part, for example, your "really happens" is going to be different if you are currently working under Agile. To avoid info-overload I've tried not to explain everything at once, but of course that means valid points have to wait until later.
The book does take the time to provide alternates at many points. It should explain "what really happens," but it first does that for waterfall, then spiral, and agile, etc. If you are reading the waterfall part, for example, your "really happens" is going to be different if you are currently working under Agile. To avoid info-overload I've tried not to explain everything at once, but of course that means valid points have to wait until later.