KG has clearly slowed down and may not be a star offensively, but he still has the capability to be a defensive star. He's probably still the best pick and roll defending big in the league. Nobody knows how to show and get back and cover the lane like he does. Also, if we ever have to go to that zone we used in the second half against Miami, he's the perfect player for that role of being the guy in the middle. Unlike in college, you don't just need a clog, but a long, smart defender who knows how to move his feet to avoid illegal defense.
Tyson Chandler is probably the closest guy to KG defensively right now as a pick and roll defender and lane coverer. At least, he was last year when he played on a team that took defense seriously. But, I don't think he's as good defensively as KG, and, of course, despite his athleticism he's still nowhere near the offensive player that KG is.
Tyson Chandler just got paid big bucks to be the final piece to make the Knicks a contender. Yet, we are going to say that KG is done. I'm sorry I guess the definition of "done" is eluding me.