Identifying Ray Allen as one of the reasons for the HEAT's poor defense doesn't actually identify the team's problem but it does identify the problem with plus-minus statistics.
The theory that Ray Allen was hurting the HEAT defense was brought to my attention on Twitter.
Ray Allen's defence may be hurting the Miami Heat: probasketballtalk.nbcsports.com/2012/11/14/wha… @mia_heat_index @uptownreport
— Karole C (@KaroleCuddihy) November 16, 2012
It's a ludicrous assumption based on a flawed statistic - plus-minus. Using a statistic that reflects the actions of 10 players on the floor to blame 1 player is retarded.
There are 2 big problems with the theory that Ray Allen's defense is hurting the HEAT.
According to mysynergysports.com, the HEAT have defended 1,101 plays this season. Only 84 of those plays were defended by Ray Allen. The only way 7% of the defense could be responsible for the HEAT giving up 8.4 more points per 100 possessions than last season is if they switched the scoring rules from basketball to football when Ray Allen checked into the game.
According to mysynergysports.com, 40.5% of the plays Ray Allen defended were spot-up jumpers and he ranks 23rd in the NBA defending those. Anyone watching HEAT games or looking at the HEAT stats can tell that spot-up threes are KILLING the team.
According to basketball-reference.com, the biggest change in the HEAT's defense is opponent shooting efficiency. Last season the HEAT ranked 8th in opponent shooting efficiency at 47.9%. This season they rank 27th at 50%.
There hasn't been a big change in opponents' shooting percentage on 2-point shots. According to teamrankings.com, last season HEAT opponents made 46.1% of their 2-point shots and this season they're making 46.9% of their 2-point shots. The problem is opponents are making 3-point 38.6% of their 3-point shots this season when they only made 34.8% last season.
So the HEAT are allowing teams to shoot better spotting up from three-point range, but Ray Allen's spot-up defense is some of the best in the NBA. The HEAT defense is allowing 1.16 points per shot from behind the three-point line but Ray Allen is only allowing 0.97 points per play on spot-ups.
Ray's not the problem with the HEAT defense. He's just another example of why plus-minus is a shitty tool for evaluating individual players.
If you want to figure out what's wrong with the HEAT defense, watching video of Chandler Parsons score his career-high is a good place to start.