My PO box has been rather lacking in anything educational from CASA since the non towered aerodrome changes.
Aha! That's the problem then, you're supposed to look at that page on their website that looks a bit like one of those 'ideas diagrams' your old English teacher used to put up on the blackboard, I forget what they're called, with thought bubbles everywhere for each part connected up with multiple lines.
Makes it all abundantly clear!