JonathanB,
You're right in that most of Mode S capabilities are not yet used by many service providers - transponder settings, etc etc - but I got the impression that the way the NATS info pack was written was aimed at looking to the future, and so was pointing out what it will be like once you're probably valid.
NATS are primarily concerned with Enhanced Mode S as this is being used in the London TMA and a lot of the traffic is the big commercial stuff rather than GA. Apologies for not including a caveat that this wasn't all happening now, and was more NATS focussed info.