Omer Asik not better than DJ Agent? Joke right? 2nd or 3rd best rebounder in NBA and a superb post defender who's incredibly physical. Sure his offense isnt much better than DJ's but his defense, rebounding and IQ obliterate DJ.
Asik brings a lot of similar problems, is a worse finisher than DJ, and without a solid defensive system doesn't look that much better defensively. He shot a career high 56.5% FT. He's just as likely to digress in his FT shooting like DJ did this season. He was at 45.6% and 50.2% the previous two seasons.
His blocks /36 went down from 2.5 to 1.3, most likely because he couldn't be as big of a shot blocking threat without fouling (this is with the understanding than more blocks doesn't necessarily mean good defense, but it could). GREAT rebounder, which is one of his biggest defensive impacts. 31.0 DRB%, that's just superb.
He anchored a 16th ranked rockets defense his DRTG was 3.1 pts/100 better than the team defensively. According to on/off numbers, Houston was 5.8 pts/100 better defensively with him on the court. Of course who comes off the bench for you matters and having poor defenders off the bench will make you look better as opposed to good ones.
DJ "anchored" an 8th ranked defense and his DRTG was 3.6 pts/100 better than the team defensively. According to on/off numbers, Clippers were 6.4 pts/100 worse on defense with DJ on the court.
Of course DJ was on the court with poor defenders like Butler, Billups, and even Blake who was only average at best, while the bench consisted of good defenders like Bledsoe, Barnes, and Odom. To get a better feel:
Blake: defense 8.1 pts/100 worse with him on
Billups: defense 7.2 pts/100 worse with him on
Paul: defense 5.4 pts/100 worse with him on
Butler: defense 5.3 pts/100 worse with him on
DJ played 2008 minutes during the season. He was on the court for about 68 total minutes WITHOUT Blake.
Then you ask, what about Odom, he had a 99 Drtg, played with Blake a decent amount too. The team was 9.7 pts/100 better defensively with Odom. Odom played 325 minutes / 1616 with Blake on the floor. 75 minutes with Butler, and 42 of those were also with Blake, and was never on the court with Bullups.
Yes, if you play with all the better defenders and avoid playing with all the bad/mediocre ones, you will have better defensive numbers than someone who is mainly playing with the poorer defenders.
Asik is an improvement in rebounding and overall defense. Defense is a team issue though, and he's not a KG type to change that alone, and even KG could only do so much with some of the Minnesota teams. He's worse offensively, a worse finisher, also clogs the lane and he's similarly bad as a FT shooter. You're placing too high expectations of how much he would help this team. It wouldn't be the difference between 56 games and 60 games, though it could arguably have helped against Memphis.
Asik's regression on blocks is largely due to the ridiculous pace that the Rockets play at. Blocked shots is not really a good indicator of anything anyway and often says little about how good you are on defense. Asik is no KG but what kind of comparison is that anyway? KG is arguably still the most impactful defender in the league by a per minute basis. Asik is still miles better than DJ on defense. As for the anchoring the defense argument. The Rockets have worse individual defenders than we do and its hard to anchor a defense when you play at such a fast pace.