A few things about Spoelstra's defensive system have been bothering me a lot, especially since 2010. Yeah, the defense has been one of the best in the league, but at what cost ? I think you could achieve similar results with far less effort or have a much better D with similar effort.
So here are my thoughts about it:
1. Let's get the excuses out of the way: "he inherited the system from Pat Riley" is the top excuse of Spoelstra's fans whenever his system is criticized. That might be true, but Riley adapted his system and his coaching to fit the players that he had. He ran the showtime Lakers as well as one of the most thuggish D's the league has ever seen in NY. You can't run the same system that you ran with Ewing or Zo when you have Bosh or Joel at C.
Another thing is: when Riley's D's were no 1 in the league, teams were shooting half the 3p's they're shooting these days and you could hand check people.
2. Showing up so hard on ALL pick and rolls is extremely demanding and is destabilizing the whole defense. It kills players physically and can't be sustained over the course of a season + playoffs. Players are routinely scrambling back to find their men and have to put a lot of energy into recovering and covering corner shooters. If a team can move the ball and shoot the 3, the Heat will get exhausted chasing them around. You can win a game or a series, but as we saw last season, at the end the players legs were dead, the J's weren't falling anymore and they couldn't keep up the defensive pressure either.
Not to mention showing up on p&r when the opposing PG/ball handler is not a good shooter is just stupid. Just go under the screen.
Edit: Forgot one thing: fatigue means players are more likely to get injured. When you worked so hard and sacrificed a few years to get 3 stars on the same team, running them into the ground is not quite the smartest idea.
3. It leaves players out of position for defensive rebounds/boxing out. How come the Heat give up so many off rebounds ? Why are Bosh's rebounding numbers so much worse than in Toronto ? Scrambling all around the floor chasing the ball like a stupid dog will leave you out of position for the rebound.
4. It's a very predictable D, so once you figured out how to beat it, it's just a matter of executing till the Heat's players legs give out. You need to do 3 simple things: move the ball, shoot the 3 well and crash the offensive boards. I had the Pacers in 6 even before Bosh went down with an injury because this is exactly what the Pacers are doing and how they beat the Heat in the regular season this season and the one before.
5. It doesn't take advantage of the personnel. Your best line-up was supposed to have 5 guys between 6'4 and 6'10 (with the 6'10 guy a very mobile one). Why show so hard on pick and rolls when most of the time you can switch ? What's the point of having so many versatile players if you're not using their versatility ?
You can switch most of the time and only come help when you get a really unfavorable match-up. That would lead to far less scrambling and a much more efficient defense, with less energy spent running all over the court.
6. It doesn't take advantage of the changes in the rules and game style. As mentioned before, these days you can play a zone but you can't hand check people anymore, and teams are shooting twice as many 3's.
You have guys that would be pretty good in a zone: long and fast, they can go out to the 3p line and back to stop penetration. Many teams in the NBA have no idea how to attack a zone. Especially if they don't have shooters or their shooters are cold. If you're faced with a team that pounds the ball inside or penetrates a lot or uses the p&r all the time, just play some zone and see if they hit contested long 2's and 3's just as well as they do layups.
So why not play zone ?
The Mavs used a lot of zone last season and they were the 8th best defense in the league despite playing some guys that were old and/or slow. I think the Heat can do much better with the players they have while also allowing them to keep some energy for the offense.
My conclusion:
You know the saying:
If all you have is a hammer, everything looks like a nail
That's Spoelstra.
He doesn't have anything but a defensive system he supposedly learned from Pat Riley (although I think he never really understood it and he's just mimicking it like a parrot) so he applies it to all the problems he faces. You can see it in his speeches, in his post-game conferences: the system is good, you just need to work harder, keep grinding, don't let go of the rope. That's basically saying "the hammer is good, just strike harder with it". That's hardly the response of someone that has more tools in his toolbox.
The Heat's defense has been good on talent and effort alone, just like the Heat's offense, without much (if any) help from the sidelines. But talent and effort will only take you so far, and when you play against team that has similar talent and are also giving their best, it's coaching that makes the difference. Not only the coaching done in the game, but the coaching done throughout the season, stuff like resting your players, saving your players' legs for the postseason etc. That's why the Spurs look so good now and Lebron and Wade look broken and exhausted, even though Duncan is about 10 years older than Lebron.
One last thing: for all those saying that the team should win even with Spoelstra as coach, you're severely underrating the importance of a coach for a basketball team. In fact, I plan on writing a post detailing how important coaches are to a team's title aspirations.
