Being a long time critic of AP, I have to say that I am pretty impressed in the significant improvement in tracking events for parcels over the past year or so. 

As a buyer and a seller, I really don't care about what mailing sorting centre my parcel goes through, if they are scanned at lodgement and at delivery thats fine by me.  The onboard for delivery scan is a bonus.

I imagine that if all parcels were scanned every single step of the way that this would have the detrimental impact of slowing delivery time down, and ultimately the additional handling surely must add to the cost of post.

AP do not commit to scanning every event in their terms and conditions.  If they did, then thats a different story, but they never have.

I still get the occassional parcel that misses a delivery scan, but this is becoming less and less frequent.