The most impressive thing to me about LeBron is his peak-level performance. LeBron's an incredibly tough guy to pin down in terms of a one-year peak; partly because his game has evolved as he's had different situations around him, and partly because he's got more truly historically great seasons than anyone else still on the board.
This recent thread asked people to rank LeBron's 5 best seasons (09, 10, 12-14), and there wasn't a huge consensus. Most had 09, 12, and 13 as the top 3 in some order and 10 and 14 below, but all five are all-timers in their own right. Just looking at the worst of those, in 2010 he averaged 29.7-7.3-8.6 on .604 TS%, good for a 31.1 PER and .299 WS/48 (both PER and WS/48 rank in the top 10 single-season marks all-time), and in 2014 his numbers slipped a bit, but he led the league in RAPM, then had one of the greatest playoff runs ever (.668 TS%, 31.1 PER).
Looking at raw totals, LeBron's longevity is on the lower end, but certainly not devastatingly so. He's now up to 33276 career regular-season minutes. Magic had 33245. Bird had 34443. Jordan played 35887 in Chicago. In terms of per-minute impact, I'd put LeBron closer to the Jordan end of that scale than the Magic/Bird end, too. As a result, LeBron already looks great by cumulative statistics. He's 15th overall in career win shares, well above Magic and Bird, who played roughly the same amount of minutes but at a lower level. He's also ahead of Hakeem, even though Hakeem played much longer than LeBron. Looking at things that reward a concentrated distribution of value a bit more (as championship odds do), he's 3rd overall in MVP shares, behind only Jordan and Kareem (some bias towards recent players there with deeper ballots, but as the majority of Bron's shares come from 4 near-unanimous MVPs and an unquestioned 2nd-place finish, he didn't gain from them as much as, say, Kevin Durant did). He's also 6th in RPOY shares (behind Russell, Kareem, Jordan, Wilt, and Magic).
In the playoffs, LeBron is a bit behind the most decorated greats with super teams in terms of longevity, but five finals runs will take you pretty far. LeBron has played 6717 playoff minutes. Magic, Wilt, Russell, and Jordan all played around 7500 each (disclaimers about number of rounds obviously apply for the old-timers). Bird is at 6886. Olajuwon, whose playoff performance is perhaps his strongest argument, only played 5749, and Dirk, who similarly is boosted for great playoff performances, only has 5544. In terms of total value accrued in the playoffs, then, LeBron holds up just fine. He's fourth in career playoff win shares, behind only Jordan, Duncan, and Kareem (all the disclaimers about shorter playoffs for old-timers count double here, as the first round is when you get the easiest wins, but still very impressive to be ahead of Shaq and Hakeem here).
I stuck to cumulative metrics above not because they're the best way to evaluate players (they're not), but rather to illustrate that even if we choose the method that is most harmed by a lack of longevity, LeBron can still hold his own. If we look at per-minute and per-possession numbers to look directly at the level of play LeBron is giving you while he's on the court, nobody else can really compete. No matter what aspect you look at, LeBron is as good as anyone.
Box score statistics: averages of 28-7-7 per game on .580 TS% in a very slow era over his last 10 years (excluding only rookie year), with very steady production year-to-year other than steadily increasing shooting efficiency. Four of the top 11 years in WS/48, and Jordan, Kareem, and WIlt have other seven. Four of the top 11 seasons in PER, and again only Jordan, Kareem, and Wilt beat him even once. If you prefer career averages, LeBron is 5th overall in WS/48 (behind only Jordan, Robinson, Wilt, and Paul), and 2nd in PER (behind Jordan, and only by .1 points). Those numbers are boosted by not yet including a decline phase, but LeBron has such a huge lead it's hard to imagine him falling far at all, especially when we see that his peak and prime is so much higher than almost everyone else.
Plus-Minus data: RAPM and similar metrics have all consistently had LeBron as on par with KG and Shaq as the very best players of the era. His peak is as high as anyone, and sustained over many years. Even some multi-year samples that include a lot of pre-prime LeBron and exclude some of his best years (i.e.
the 02-11 RAPM on Colts' site) has LeBron as the #1 player of the era, with a 1-point lead over his only challenger in KG and a 3-point lead over Duncan, Kobe, Dirk, Wade, and Nash, even with a sample just about perfect for grabbing their primes and little else. Data from his (rare) missed games in Cleveland and consistently great raw on-off numbers only back this conclusion up. The eye test, while not computationally as powerful as RAPM, can also tell that LeBron's impact would hold up beyond basic stats. He's an excellent passer, and spaces the floor very well (especially when at the four), two of the most important things for +/- data that may slip through the box score. In contrast to someone like Wilt, who was known for chasing stats above all else, LeBron's defining trait might be "making the right play", rejecting the hero-ball narrative and getting his teammates involved, even with the game on the line.
Defense: This is harder to measure than some of the other stuff, and LeBron is obviously not Hakeem/Duncan level here, but he's still one of the
great perimeter defenders of all time. By every measure I've seen, whether in the box score, plus-minus data, or popular acclaim, LeBron rates out very well. His size and athleticism make him very versatile, and without that versatility from him (and, to a lesser degree, Wade), I doubt the Heat's trapping style would work at all. I rate LeBron's defense as similar to that of Jordan or of Kareem, Shaq, and the second or third tier of defensive bigs, and it's in that half of the game that he really separates himself from Magic and Bird, average at best players on that end.
Playoff performance: This is one area detractors harp on with narrative-based attacks, but even with a couple hiccups (like everyone has once you've ranked Jordan and Russell), LeBron's performance is as good as anyone's. He won
two finals MVPs in very convincing fashion, and was the best individual player in this year's finals, too (admittedly, this was in much less convincing fashion). He's third in career playoff WS/48 and PER, behind only Jordan and Mikan in both cases. I don't have his numbers in elimination games at my fingertips, but I've seen them posted many times, and they are incredible. He might be the all-time leader in PPG in elimination games, or behind only Jordan, if I recall correctly.
Off-court issues: LeBron has been basically a model citizen in this regard. Some fans perceive him as having a large ego and judge him harshly for it, but in terms of building a camaraderie among teammates and a happy environment, LeBron is excellent here. The chemistry in Cleveland and Miami were both clear even to outside observers, and the teams just loved playing together. This isn't a super important category (unless you really screw it up), but there are no concerns here for LeBron. If you're going to hold leaving as a free agent and going to Miami against him, then you better knock Oscar Robertson a long way down your rankings , as he's responsible for enabling decades of such behavior with his lawsuit.
Clutch Performance: Part of this is covered in his playoff performances, and another part is about how he performs in late-game situations. Some fans knocked him for this due to his famously passing up some shots to get teammates wide-open threes on the final possessions of the game. The evidence just doesn't back them up, though. What's crazy is, I want to say they're wrong because "hero ball doesn't work; you should just make the right basketball play and find the open man", but that's not entirely accurate. It's more like "Hero ball doesn't work, unless you have LeBron". League efficiency tends to go down in those scenarios, but LeBron's shown a propensity for incredible clutch performances over the years. 82games has been tracking clutch stats for the past six years, with clutch defined as "4th quarter or overtime, less than 5 minutes left, neither team ahead by more than 5 points". By their numbers,
in 08-09 LeBron averaged 55.9 points, 14.3 rebounds, and 12.6 assists per 48 minutes of clutch time, on .556/.421/.85 shooting splits (.693 TS%). Cleveland outscored their opponents by 103 points in 111 minutes of clutch time that year, or +45 per 48 minutes.
In 09-10, he averaged 66.1-15.9-8.3-3.2-3.2 per 48, on .488/.340/.80 shooting (.630 TS%). Cleveland outscored their opponents by 116 points over 151 minutes in those situations, or +37 over 48 minutes. After relative down years (by his standards), LeBron picked back up at a pretty great pace
in 12-13, when he averaged 38.7-15.2-14.9 per 48, on .442/.280/.76 shooting (.555 TS%). While the individual numbers aren't as crazy, Miami outscored opponents by 125 points over 161 minutes of clutch time with LeBron, or +37 per 48 minutes, and this was a big factor in their 26-game winning streak. They could basically take it easy for much of the game, then turn it on in the second half if they needed to and overcome any deficit they might've accrued. I generally don't believe there's much merit to clutch performances, but this is stuff that just should not be possible. 66 points per 48 on .630 TS% for a slow team in the modern NBA, in the most important time of the game? Outscoring opponents by about three or four times as much per minute as the best season-long marks in NBA history, entirely in game-deciding moments? If anyone tries to tell you LeBron wasn't clutch before coming to Miami, or before the 2012 championship run, they could not be more wrong.
Team Success: While *only* having two titles might put him behind some of these guys, LeBron has led some very successful teams using very different styles. He led a 66-win, 8.68 SRS Cavs team in 2009 that almost always had two bigs on the floor and used their size to their advantage, with basketball-reference saying LeBron was at SF 74% of the time. The team had a +10.0 efficiency differential, which actually increased to +15.0 with LeBron on the floor (compared to -6.2 while he sat, a net difference of 21.2 points). He went to Miami, and peaked there with a 66-win, 7.03 SRS team in 2013. That team was all about surrounding LeBron with shooters and spacing the floor, and used LeBron at PF in 82% of his minutes (and at C in another 9%). Their +8.6 efficiency differential increased to +13.2 with LeBron on the floor, compared to -2.1 when he sat (a net difference of 15.3 points). That's very impressive versatility, leading two entirely different 66-win teams, both as the unquestioned #1 man (and near-unanimous league MVP), and doing it in not only two different roles but at two different positions entirely.
