Anon, I made that post when he was 1/4 from the field and had just had several defensive brainfarts in a row. He was a little more aggressive and assertive, and less dribble-out-the-shot-clock-happy in the 2nd half but his defence remains fucking awful.
The thing with Patty is, it's not effort related like it is with most heat-check NBA players: he's in every play, he's bumping guys with his chest, he's busting his ass running around screens, he is hustling to stay in front of his man...he just has no idea how to play defense at all. It's a whole lot of wasted effort.
He plays ballhandlers waaay to close and gets routinely burned despite being the fastest player in the league according to Sport VU. He goes for the flop first and everything else comes second. He gets posted up by opposing PGs regularly with disastrous results. He misses rotations as a routine.
This stuff doesn't really make too much of a difference in his sparkplug role (i've never seen Jamal Crawford or JR Smith play defense either...), but you notice it more when he gets extended burn and has to play against opposition first units. If he wants playoff minutes he needs to be able to guard his position a lot more effectively and not rely on the help every time down the floor.