I think it's important to note that Iverson can play defense when the mood strikes him. He did for Larry Brown in Phily. Put him in a tough Detroit squad full of capable defensive players and he could raise his D in a big way. Iverson has been dogging it for the last few years on the defensive end, but he is a capable defensive player.
He played the passing lanes. Philly had defensive players at every other position and a big shot blocker (ratlif then Mutumbo) to cover for AI.
It worked in the weak east then. It hasn't worked since. Certainly not going to work against Boston who has guys that will hurt them if they have to scramble to cover for AI playing the passing lanes.
Iverson did more than play the passing lanes. It wasn't a constant but he did play good all round defense at times under Larry Brown. He's capable of being a good defender.
I remember games where Iverson held Kobe to something like 10 points and 30% shooting
(Kobe did the same to him). The season they made the finals he played quality defense, especially the first half of that season
(before a larger offensive burden was on his shoulders).
I'm not a fan of Iverson, I think he's overrated as a player and that he does a lot of things that hurts his teams. But I also think it's important to say he's capable of playing good defense and has done so in the past .... and that it's premature to write him off defensively before he suits up for the Pistons. He might surprise us and start putting effort in on that side of the floor once again.
Iverson is capable of playing good defense when he puts his mind to it ... which does not happen nearly often enough.