Saw some discussion on James's defense a few pages back, so I'm posting this here (from PC Board).
SideshowBob wrote:I've seen a few people ask about Lebron's defense, and thought this might be a good time to get to it.
He's a guy who anchors the half-court defense from the perimeter by: covering as much of the floor as possible (horizontal game), playing disciplined within sets and forcing others to do the same (team defenses are designed to reduce overall opposing offensive efficiency, therefore, staying true to the system on a team level tends to produce better defensive results than an individual exerting effort on stopping an opposing individual), using his combination of length and quickness to rotate and recover VERY fast, using his versatility in defending the PnR as he can cover both the handler and the roll-man and be effective on the switch with virtually any combination. On top of that, he's also decent weak-side shot blocker, and has a great knack for playing the passing lanes.
This kind of defense:
A.) Creates a ton of turnovers. Miami is currently #8 in the league in oppTOV% and is trending upwards (they were #16 just a week ago). Last year, they were #3. In 2011, they were only #26, and the 2010 Cavs were only #24, but the 09 Cavs were #10.
Opponent TOV% with Lebron on the floor
Miami
2013: #1 (16.7%)
2012: #1 (18.5%)
2011: #5 (14.5%)
Cleveland
2010: #5 (14.3%)
2009: #1 (16.2%)
B.) Decreases efficiency on all shots away from the rim. Because of his length, quickness, and discipline on the perimeter, he usually helps anchor a perimeter defense that traps aggressively, prevents penetration, recovers quickly (shots are almost always at least partially contested), and is backed up by an smaller interior defense that denies position (also one of James staples). This forces either contested shots, or forced low-percentage shots. Lebron's defenses tend to allow much more attempts from 10-15 feet on average, while forcing all shots inside the 3-point line to be low-percentage.
In 2012, they allowed the 10th most attempts from 10-15 ft, but gave up only 35.7% of them (6th best). From 16-23 feet, they allowed the 19th most attempts, but gave up only 37.6% of them (12th). This year, they allow the 13th most attempts from 10-15 ft, but give up only 36.6% of them (3rd best). From 16-23 ft, they allow the 25th most attempts, but give up 36.6% of them (10th best). I'd delve into more seasons, but Hoopdata's site is being a pain right now.
C.) makes it difficult for the opposing offense to GET good shots and positioning near the rim. Again, here, its his versatility that comes into play. The perimeter defense he anchors and his smarts on the PnR make it difficult for the ball to get inside. On the flip side, his strength and length are often a great tool for ball-denial and single-coverage in the post. He's great at fronting guys and this can often take the league's better post scorers out of offensive action, instead of forcing them into bad shots. When they're able to get the ball, they still draw the attention of the defense, which creates offensive rebounding opportunities, easy buckets for off-ball guys on the move and open shots for guys on the perimeter. In these situation, James's man defense becomes important, because its often in the defenses best interest for him to force the player into a bad shot.
HOWEVER, when he forces ball-denial, it can throw the entire opposing offense out of whack. In sets designed to take advantage of an inside scorer (in the manner described above), James's aggressive fronting does a couple things. He forces precious time off the shot clock, giving less time for the rest of the team to create something, which tends to lead to a higher percentage of bad or contested shots OR turnover. He also likely denies the opposing offense their primary method of attack in the running play, forcing them to either start fresh, or exhibit some sort of counter or wrinkle, which again, tends to lead to a high probability of decreased offensive efficiency.
Again, we can see evidence of this in the team based stats.
Opponent FG% at Rim
Miami
2013: 61.6% (6th best)
2012: 57.7% (2nd best)
2011: 58.0% (1st best)
Cleveland
2010: 58.3% (6th best)
2009: 59.3% (6th best)
Keep in mind, this is without ANY prominent shot blockers on these teams. James was actually the team leader in total blocked shots in those two Cleveland years, and Anthony has typically been the leader in Miami, with just over 1 per game.
Opponent eFG% with Lebron on the floor
Miami
2013: 48.3% (#10)
2012: 47.7% (#8)
2011: 46.9% (#2)
Cleveland
2010: 48.2% (#3)
2009: 46.4% (#1)
Now, the last thing I'd get to is transition. Here, James is arguably the best in the league. He's typically extremely active in transition; he creates turnovers independently, we've seen him often just grabbing the ball out of the handler's hands, but he's also frequently looking for poorly timed passes. Furthermore, he's known for his shot-blocking on the break, which I'm starting to believe is getting a bit underrated.
Firstly, he's creating hesitation on the break and in transition this way. Transition baskets are generally the highest percentage baskets in the game; however, Lebron's shotblocking threat here can affect efficiency, which is crucial as its turning near-100% buckets into slightly lower ones. If that doesn't happen, we'll see the handler often slow it down to avoid the shotblock, and instead wait for the rest of the team to arrive in order to engage the offense. Again, this is always going to be less efficient in the long run than getting an easy transition bucket.
Second and less importantly, notice that he tends to block the shot directly off the backboard, which oftentimes not only allows Miami/Cleveland to maintain possession of the ball, but frequently triggers a fastbreak in the other direction. Even if this doesn't occur, the opposing team will almost ALWAYS be in a poor position to get into proper defensive positioning, and I'd wager that Miami/Cleveland's offensive efficiency on possessions after a Lebron chasedown block is noticeably higher than average. This is literally creating OFFENSE out of DEFENSE.
All-in-all, James is arguably the most dynamic defender in the league, and I can make this claim without giving his positional versatility much prominence at all. His overall contributions on help-defense and dominance in transition make him among the most impactful non-big defensive player in the league, and for that matter, he's better than a lot of elite prototypical bigs as well.
Note that I'm posting this strictly to add to the earlier discussion, not to make Lebron's MVP case, seeing as I have Durant over him (though just barely).