i get items delivered quite regularly with sign for, prolly cos i know the postman quite well i never look to see if the parcels are addressed to me until after hes driven away. 

it ought to be a requirement that before signing the postman/woman/person should show the parcels address label to the person about to sign for it just to be sure its the right place.

would stop most of the wrong address deliveries on the head (signed for ones that is)