Editor's note: not sure who this new guy is but wow, this is pretty great. Make sure you read.

"Defense wins championships."

"You can't win it all without a top-10 defense."

Many people believe this to be true. But what does the data show? How good does your defense really need to be to have a legitimate shot at the winning the championship? And what about offense? Which one is more important?

In order to figure this out I compiled a data set consisting of the ORtg, DRtg, and Net Rating of every team since the 3-point line was instituted in the 1979-80 season. Next, I calculated the standard deviation for the population of each season. Then, for each team, I calculated how many standard deviations better or worse than the league average they were in ORtg and DRtg. For example:

2013-14

Key -

Blue = NBA Champion

Purple = Runner-up

Bold = Conference finalist

Net = ORtg - DRtg

Off = Number of standard deviations a team's ORtg is from the mean

Def = Number of standard deviations a team's DRtg is from the mean

Tot = Sum of the 'Off' and 'Def' columns

This method is more accurate than simply ranking offenses and defenses 1, 2, 3… For example, this method shows us that in 2013-14 the difference between the #1 defense (IND, +2.33) and the #5 defense (CHA, +0.90) was less than the difference between the #5 defense and the #21 defense (DEN, -0.49). It measures exactly how good a team is in relation to their contemporaries.

It is also more accurate than simply comparing the ORtg & DRtg of teams from different eras. In the last 35 years, the average ORtg & DRtg for a season has peaked as high as 108.3 in 1986-87 and dropped as low as 102.2 in 1998-99. The best defense in the league in 1986-87 would have ranked #22 in the league in 1998-99 if we simply used DRtg to compare the teams. Using the method outlined above, however, the #1 defense in 1986-87 would have ranked #2 in 1998-99.

This method is not perfect, as it does not account for the ebb and flow of talent in the NBA at any given time. After all, not every defense played against a Michael Jordan-led offense, and not every offense played against a Tim Duncan-led defense. But it is reasonably accurate, which makes it suitable for answering the questions outlined at the outset.

Offense & Defense Rating Scale (Off & Def columns) -

+2.00 or more = Historically Elite

+1.50 to +1.99 = Elite

+1.00 to +1.49 = Very Good

+0.50 to +0.99 = Good

+0.01 to +0.49 = Above average

-0.01 to -0.49 = Below Average

-0.50 to -0.99 = Poor

-1.00 to -1.49 = Very Poor

-1.50 to -1.99 = Terrible

-2.00 or less = Historically Terrible

These 'grades' are somewhat subjective, but hopefully this lends some context to the numbers I'll be using throughout this article.

By adding the ORtg value and DRtg value together we can create an overall team rating. The scale for that is a little bit different:

Overall Team Rating Scale (Tot column) -

+3.00 or greater = Historically elite. 8 teams, 7 conference finalists (88%), 6 champions (75%).

+2.50 to +2.99 = Championship favorite. 26 teams, 19 conference finalists (73%), 9 champions (35%).

+2.00 to +2.49 = Legitimate contender. 60 teams, 39 conference finalists (65%), 7 champions (12%).

+1.50 to +1.99 = In the picture. 72 teams, 32 conference finalists (44%), 7 champions (10%).

+1.00 to +1.49 = Long-shot. 102 teams, 29 conference finalists (28%), 5 champions (5%).

+0.50 to +0.99 = Nearly impossible. 110 teams, 8 conference finalists (7%), 1 champion (1%). The lone exception: 1994-95 Houston Rockets when Hakeem Olajuwon elevated his play from MVP-caliber in the regular season to Destroyer of Worlds in the playoffs.

No team below this level has won a championship in the modern era.

Now let's examine some historical precedents for NBA Champions.

NBA Champions

Year NBA Champion ORtg DRtg Net Off Def Tot 2013-14 San Antonio Spurs* 110.5 102.4 8.1 1.22 1.34 2.56 2012-13 Miami Heat* 112.3 103.7 8.6 2.06 0.68 2.74 2011-12 Miami Heat* 106.6 100.2 6.4 0.62 1.36 1.98 2010-11 Dallas Mavericks* 109.7 105.0 4.7 0.75 0.69 1.44 2009-10 Los Angeles Lakers* 108.8 103.7 5.1 0.38 1.19 1.57 2008-09 Los Angeles Lakers* 112.8 104.7 8.1 1.49 1.16 2.65 2007-08 Boston Celtics* 110.2 98.9 11.3 0.79 2.49 3.28 2006-07 San Antonio Spurs* 109.2 99.9 9.3 0.95 2.26 3.21 2005-06 Miami Heat* 108.7 104.5 4.2 0.80 0.54 1.34 2004-05 San Antonio Spurs* 107.5 98.8 8.7 0.44 2.24 2.68 2003-04 Detroit Pistons* 102.0 95.4 6.6 -0.26 2.13 1.87 2002-03 San Antonio Spurs* 105.6 99.7 5.9 0.60 1.19 1.78 2001-02 Los Angeles Lakers* 109.4 101.7 7.7 1.58 0.91 2.49 2000-01 Los Angeles Lakers* 108.4 104.8 3.6 1.73 -0.57 1.16 1999-00 Los Angeles Lakers* 107.3 98.2 9.1 1.02 1.84 2.86 1998-99 San Antonio Spurs* 104.0 95.0 9.0 0.51 2.06 2.57 1997-98 Chicago Bulls* 107.7 99.8 7.9 0.72 1.41 2.13 1996-97 Chicago Bulls* 114.4 102.4 12.0 2.27 1.24 3.51 1995-96 Chicago Bulls* 115.2 101.8 13.4 2.22 1.72 3.94 1994-95 Houston Rockets* 109.7 107.4 2.3 0.46 0.27 0.73 1993-94 Houston Rockets* 105.9 101.4 4.5 -0.11 1.48 1.37 1992-93 Chicago Bulls* 112.9 106.1 6.8 1.63 0.64 2.27 1991-92 Chicago Bulls* 115.5 104.5 11.0 2.39 1.19 3.58 1990-91 Chicago Bulls* 114.6 105.2 9.4 2.12 0.84 2.96 1989-90 Detroit Pistons* 109.9 103.5 6.4 0.53 1.38 1.91 1988-89 Detroit Pistons* 110.8 104.7 6.1 0.88 0.91 1.79 1987-88 Los Angeles Lakers* 113.1 107.3 5.8 1.59 0.24 1.83 1986-87 Los Angeles Lakers* 115.6 106.5 9.1 2.35 0.59 2.94 1985-86 Boston Celtics* 111.8 102.6 9.2 1.54 1.54 3.07 1984-85 Los Angeles Lakers* 114.1 107.0 7.1 2.22 0.31 2.54 1983-84 Boston Celtics* 110.9 104.4 6.5 1.24 1.21 2.45 1982-83 Philadelphia 76ers* 108.3 100.9 7.4 1.03 1.08 2.10 1981-82 Los Angeles Lakers* 110.2 105.5 4.7 1.03 0.43 1.46 1980-81 Boston Celtics* 108.4 102.6 5.8 0.99 1.01 2.00 1979-80 Los Angeles Lakers* 109.5 103.9 5.6 1.59 0.51 2.10 110.0 102.7 7.4 1.18 1.13 2.31

- Both offense and defense matter. The average champion was +1.18 on offense, +1.13 on defense, and +2.31 overall.

- You can't ignore one side of the ball. Only 3 times in 35 years has a champion been below average on one end of the floor: the 1993-94 Houston Rockets (-0.11 Off / +1.48 Def), the 2003-04 Detroit Pistons (-0.26 Off / +2.13 Def), and the 2000-01 Los Angeles Lakers (+1.73 Off / -0.57 Def).

- You can be merely above average on one end. 16 champions had an offense less than one standard deviation from the mean. 15 Champions had a defense less than one standard deviation from the average. In most cases, these teams were elite on the other end of the floor.

- You can't be merely good on both ends. Only 4 times in 35 years has a team won the title without being more than a standard deviation better than average on either end of the floor: the 1988-89 Detroit Pistons (+0.88 Off / +0.91 Def), the 1994-95 Houston Rockets (+0.46 Off / +0.27 Def), the 2005-06 Miami Heat (+0.80 Off / +0.54 Def), and the 2010-11 Dallas Mavericks (+0.75 Off, +0.69 Def).

So, what is the current NBA landscape?

2014-15

Team ORtg DRtg Net Off Def Tot Golden State Warriors 111.1 100.7 10.4 1.72 1.44 3.16 Atlanta Hawks* 108.9 102.4 6.5 1.05 0.93 1.98 Los Angeles Clippers 111.7 106.0 5.7 1.90 -0.17 1.73 Portland Trail Blazers 108.0 102.3 5.7 0.78 0.96 1.73 Cleveland Cavaliers 111.6 106.6 5.0 1.87 -0.35 1.52 San Antonio Spurs 107.3 102.7 4.6 0.56 0.84 1.40 Dallas Mavericks 109.9 105.8 4.1 1.36 -0.11 1.25 Memphis Grizzlies 106.1 102.3 3.8 0.20 0.96 1.16 Houston Rockets 106.1 102.9 3.2 0.20 0.78 0.97 Toronto Raptors 110.6 107.5 3.1 1.57 -0.62 0.94 Oklahoma City Thunder 106.7 103.9 2.8 0.38 0.47 0.85 Chicago Bulls 107.0 105.1 1.9 0.47 0.11 0.58 Washington Wizards 104.4 102.9 1.5 -0.32 0.78 0.46 Milwaukee Bucks 102.8 101.9 0.9 -0.81 1.08 0.27 New Orleans Pelicans 108.5 107.7 0.8 0.93 -0.69 0.24 Indiana Pacers 102.8 102.3 0.5 -0.81 0.96 0.15 Phoenix Suns 106.9 106.5 0.4 0.44 -0.32 0.12 Utah Jazz 105.4 105.9 -0.5 -0.01 -0.14 -0.15 Boston Celtics 104.1 105.1 -1.0 -0.41 0.11 -0.30 Charlotte Hornets 100.9 102.9 -2.0 -1.38 0.78 -0.61 Detroit Pistons 104.2 106.3 -2.1 -0.38 -0.26 -0.64 Miami Heat 103.9 106.8 -2.9 -0.47 -0.41 -0.88 Denver Nuggets 103.8 107.3 -3.5 -0.50 -0.56 -1.07 Brooklyn Nets 102.9 106.7 -3.8 -0.78 -0.38 -1.16 Sacramento Kings 104.9 109.5 -4.6 -0.17 -1.23 -1.40 Orlando Magic 101.5 107.7 -6.2 -1.20 -0.69 -1.89 Los Angeles Lakers 103.6 110.1 -6.5 -0.56 -1.42 -1.98 Minnesota Timberwolves 102.5 111.1 -8.6 -0.90 -1.72 -2.62 New York Knicks 100.7 110.6 -9.9 -1.44 -1.57 -3.01 Philadelphia 76ers 94.2 104.3 -10.1 -3.42 0.35 -3.07 105.4 105.4 -0.0 3.3 3.3 5.0

First of all, Golden State is having a truly fantastic season. They grade out as elite on both ends of the court.

Next, we currently grade out as having an elite offense (+1.83), below-average defense (-0.32), and in the championship picture overall (+1.51). Not bad, but not great either.

However, since January 15 the Cavaliers have been playing much better on both ends of the court. In those 29 games the offense grades out as the best in the last 35 years (116.0 ORtg, +3.21), and it's not close (next best is +2.61). Meanwhile, the defense has improved to above-average (104.0 DRtg, +0.44). Overall (+12.0 net rating, +3.65), that would put us alongside some of the best teams ever. Even if we regressed a full standard deviation from this level, we'd still be the championship favorite in a typical year.

Of course, this isn't a typical year. The Golden State Warriors have been playing at a level nearly this good for the entire season. If we meet them in the NBA Finals one could argue that it'd be the best matchup since 1996-97 when the Chicago Bulls (+3.51, #3 in modern era) defeated the Utah Jazz (+2.81, #16 in modern era).

In conclusion, is a top-10 defense necessary? No. But it certainly doesn't hurt. Without one, a team would either need a lot of luck or to be historically elite on offense. Since we do have an historically elite offense, though, we will be a contender as long as our defense is respectable. And if we can build a very good defense in the next 1-2 years we just might have a team that could rival those 1990s Chicago Bulls.