Sounds like it doesn't only let you try again, it actually only checks if last [password length] numbers match the password (that's why he can compress it into one long number)
Right, even removing that flaw would make it closer to two hours than 20 minutes (although half that to get in on average). Significantly less if you leave finger smudges on the keys though.
That said, agreed with the above: anywhere someone fiddling with the lock for 20 minutes would go unnoticed, a brick would go unnoticed too. I highly doubt a car has even been stolen through hacking the keypad lock in this manner.
"Significantly less if you leave finger smudges on the keys ..."
Those that I have seen have this plastic covering that allows some tactical feedback (a small pop under the finger.) And people are lazy and don't change codes. So the plastic wears and even comes off, leaving the silicone exposed on the numbers that are used. Well beyond smudges, and much shorter than this 20 minute code.
