I'm purely joking above, never implied anything. But I don't understand what you are saying - that the passport is sent to you by regular mail and the post office has a record at your end of what was sent and that it was delivered to you? It's possible they can access the scanning code from each piece of mail and know the sender and addressee, but that sounds unusual to me that they are verifying individual mail. Also, does anyone know are passports sent out regular mail?
So here is the procedure I followed:
My passport was about to expire, so I took a new
passport photo of myself and sent my old passport
with some forms to the passport office.
They were supposed to mail me back the new passport
within a month in the regular mail.
It never arrived and I went to the post office and complained. After some arguments, the post office revealed that they have an internal tracking code that they use. Their records show that the passport was delivered to my doorstep.
There are so many illegal aliens who would just love a nice,shiny, new passport