For all of their collective speed defensively, the Heat force relatively few turnovers. They ranked 26th in the league in turnover rate (percentage of opponents' possessions that result in turnover).
That's not necessarily a bad thing. During their run of excellence, the Spurs have usually ranked toward the bottom of the league in forced turnovers, largely because Gregg Popovich discourages gambling for steals in lieu of a strong base defense. Erik Spoelstra follows the same principle (though often Dwyane Wade and Mario Chalmers can't help themselves).
We know the Heat thrive in the open court. In fact, they lead the league in points scored per transition opportunity. We also know that fast breaks are often the result of forced turnovers.
This poses an interesting question for the Heat: How can they generate more turnovers (and, consequently, more opportunities on the break) without sacrificing the integrity of their half-court defense?
At HoopsWorld, Coach Anthony Macri, who works with David Thorpe and the Pro Training Center, writes that the Heat are enjoying the best of both worlds right now. They haven't forced more turnovers, but they're generating a higher quality of turnover:
In their playoff series against Boston ... the HEAT is displaying a more mature and complete defensive mindset. They have progressed to add better off-ball anticipation in passing lanes, coming up with crucial steals after forcing the Celtics into odd places with their ball pressure. Boston, which has carved up teams with the ball screen all year, has struggled to find the open man out of traps and blitzes. Miami seems much better prepared for Boston's flashes and movement, and the Celtics failed to adjust to that reality in Game 2.
The quantity of turnovers forced in this series is not higher than what Miami accomplished during the regular season. However, the quality of turnover forced is much higher, and the level of interruption to Boston's normal offensive flow is markedly better. Interestingly, it is actually through less gambling and more deliberate and measured disruption that Miami has turned up their ability to force turnovers. In particular, LeBron James and Dwyane Wade have taken a more conservative approach when off the ball, staying home and providing support when needed, and not overshooting lanes in the attempt for the big deflection and runout. This gives Miami's defense more structural stability, which means players are more confident when they do see the opportunity to go for steals.
The Heat vary their defensive coverages as much as any of the league's top-tier teams, which helps them a great deal in this respect. Much of that variety can be attributed to their personnel up front. For instance, Zydrunas Ilgauskas and Erick Dampier don't have the mobility to blitz and recover, whereas Joel Anthony can jump out on a point guard and transport himself back to the paint in an instant. Chris Bosh also has the mobility to turn on a dime -- and the length to bother point guards with a hard show.
During the winter months, you could go weeks without seeing the Heat trap consecutive pick-and-rolls. Spoelstra prefers his big man to show on a pick-and-pop rather than trap (which requires the other big to pick up the popper). We've seen a far more aggressive defensive approach from the Heat in the past couple of weeks, but more than anything, we've seen a wide array of tactics.
Anthony's intuition defending the pick-and-roll is particularly strong, and his athleticism allows him to defend a pick-and-roll more aggressively, as does the knowledge that Wade and James are the defenders behind him, holding down the fort if the ball happens to work its way into the paint.