Sent validation letter on 12/30, green card is stamped 1/3/02, got it back today, 1/12/02. In the section " Complete this section on delivery " It has a place for the receipient to print their name, and to sign their name. However, no name is printed, and under signature, there are two letters, and in someones initials, i.e. MC ... Is considered acceptable enough proof in case I need to send to CRA's, or if it has to go as far as the courts?
You would have gotten it back undelivered if no one would sign for it. I think it is completely valid proof of receipt. If it actually came down to it, you should be able to find out which post office and carrier delivered it and get a statement from them.