This should be a valuable edition not to interpret FAA rules to us but to provide us with a "view from the tower". That is, what guidance ATC controllers are given, references we can view, training controllers receive and so forth. Knowing what an ATC controller is thinking - their perspective and the context - when s/he says something can be very useful for us pilots who want to be sure that our communications are clear and understood.
All of us who have flown for a while know that controllers say certain things in certain situations that have more implied meaning than is actually spoken. When you've been around a while, you sense and pick up on that. The inexperienced pilot may not.
For example, the pilot must request certain types of clearance that the controller knows may be useful but the controller is not allowed to offer, such as a contact approach (may not be applicable to SP).
Some readback controllers seem to accept even if it is not all that correctly said, but in some cases controllers want to hear the exact words. What are those cases and why does it matter? Because it's on tape? Example may be involved with "traffic in sight".
This should be a rollicking good discussion, one in which I expect I'll be the not always on the side of the angels.