Comparing the brands of basketball played during the NBA regular season and the playoffs is like judging apples against pears or describing the relationship between Spanish and Portuguese: They seem almost functionally identical at first brush, though they differ in some rather fundamental ways.
In pro hoops, the rules of the game don't change once the calendar hits mid-April and half of the league goes home. Rather, it's the nature, intensity and quality of the competition within the confines of the sport that shifts entirely once the road to the Larry O'Brien Trophy is more clearly demarcated.
Easy evenings against lottery-bound patsies are replaced by long nights against top-tier teams. Wily improvisation is eschewed for crisp execution. Fast-paced play, fueled by careless mistakes, gives way to a slower, more careful and more deliberate style wherein half-court scoring is paramount. Benches shorten. Muscles tighten. Every possession is precious. Every stop is crucial. Every miscue is costly.
Those teams that don't follow along are almost always the first to be bounced from the NBA's big dance.
To be sure, many of the current title contenders don't typically play this way during the regular season. The Miami Heat, Oklahoma City Thunder and Los Angeles Clippers (among others) are all top-notch teams that can/will have to adjust the way they play to better suit the high-pressure environment of the playoffs.
These five teams, on the other hand—while not necessarily championship favorites—are already well-attuned to the peculiarities of playoff basketball because they've employed a similar brand throughout the regular season.