You might hear that the Miami Heat are playing "small ball" now, but this is not entirely the case. Erik Spoelstra has just gained increasing comfort with playing LeBron James at power forward. The strategy is only small insofar as it takes a big player and moves him into a position traditionally played by big players.
LeBron James is not small for a power forward, though. At over 6'8" (in socks), 250 lbs, he's taller and 25 pounds heavier than, say, Josh Smith. The operational definition of "small ball" means moving a traditional wing to a frontcourt spot, and that is indeed what Miami is doing. But when you call something "small," it can be taken as pejorative, deficient.
In the case of other moves to "small ball," coaches were really sacrificing something for a speedy, sweet-shooting frontcourt. When Don Nelson would play off-guards at power forward, the strategic ploy had its negative consequences. His squads would often get killed on the glass while giving up more points than Georges Seurat.
Though this strategy had its benefits—upsetting the mighty Mavericks counts as a plus—going small had serious limitations.
Miami's small ball should be about shedding limits, not living with them. When LeBron is moved to the 4, Miami will lose nothing in rebounding or defense. With Shane Battier manning the small forward position, the Heat should not cede size either.
Here's what they gain: James should kill some slower opposing power forwards. Put Miami in a hypothetical battle against the Lakers. If James is moved to power forward, he will either offensively abuse Pau Gasol or force Pau to the bench. And before you respond by saying that Gasol will pummel James in kind, watch this:
Miami has surrounded James with the means to make this shift all the more devastating. Chris Bosh can shoot from distance, so his move to center opens up the floor for LeBron to drive. Like James, Bosh is well sized for a larger position (he's over one inch taller than Dwight Howard, for example).
Bosh is far from Miami's only shooter, too. Ray Allen should help, as should Mario Chalmers and—if he's physically able to stand like a true biped—Mike Miller.
Miami can also plausibly play Wade at the 3 in a pinch (shooting guard height, but his wingspan skirts 6'11"). Or, the Heat can put Wade at the point guard slot in certain situations. In another testament to LeBron's (and the roster's) flexibility, Miami could conceivably tell D-Wade to abuse a smaller point guard, while putting bigger players at all the other positions.
Versatility is a great asset in a league without truly defined positions. While we want to compartmentalize players as a [blank], there is no fixed rule that dictates a man's position.
Much of the league operates according to this restrictive framing though, which allows multipurpose guys like James to take advantage of the limited. Barring injury, Miami's is the most dynamic offense in the league. There is nothing small about that.