Agree with you djnish. PDI is primarily to check you are not getting a lemon and some pre delivery niggles that have skipped the dealer's PDI. There are some unscrupulous dealers who don't mind putting a PDI cleared stamp on papers prior to sending it for registration. IIRC, PDI clearance along with PUC is a pre-requisite for registration. In case of such crooked dealers, a thorough PDI is a must and am quite sure it is not too difficult to spot a crooked dealer.