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It wasn’t supposed to be this easy.

With LeBron James in Cleveland, the Miami Heat weren’t exactly expected to crater and collapse in spectacular fashion but to simply wither away—slink into mediocrity, 40-odd wins and maybe the No. 6 seed in an Eastern Conference that’s wafer thin. That was their ceiling, we reckoned.

The departed James was their linchpin, the once-in-a-generation world-beater who carried them on both ends of the floor. He wasn’t just the straw that stirred the drink. He was the straw, the drink, the bartender, the farmer who tended the rye and the bottler who sold the concoction. He was the Miami Heat.

But while the Cleveland Cavaliers have limped to a 3-3 record, the Heat have opened eyes around the league with a selfless and dynamic offense. Despite the presence of Chris Bosh and Dwyane Wade, the system has been the star. If it keeps up, the Heat might have a puncher’s chance of advancing to their fifth straight NBA Finals.

The main thing in Miami is ball movement. It’s been the key to Miami’s 5-2 start and to an attack that’s placed fourth in the NBA in offensive efficiency, per ESPN. The 2014-15 Heat are scoring 108.3 points per 100 possessions, a mark that’s almost identical to last season’s 109 figure.

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According to Grantland’s Zach Lowe, the Heat have assisted on 64.5 percent of their buckets, the second-highest mark in the league. Miami is still eschewing size in favor of a pass-happy approach that keeps defenses off balance:

They’ve adapted their pace-and-space system perfectly for the post-LeBron era. They’re playing smallish lineups, with Shawne Williams starting at power forward, spreading the floor around Dwyane Wade and Luol Deng, and pinging the ball all over the court.

As Lowe wrote, Miami has done something unusual. Rather than find a player who can do all the things James did—an impossibility—it's replicated LeBron’s production with a team effort.

This is, needless to say, a surprise. Most figured that, absent James, the Heat would run more conventional offensive and defensive sets—that Miami’s system couldn’t go without its former principal. So far, we’ve been proved wrong.

“The principles are the same,” Erik Spoelstra told Lowe, though he suggested Miami had made some tweaks to accommodate new talent. “How we do it is different.”

The question at this point isn't whether Miami can win big, but if it can keep it up—eventually forcing its way into the contender conversation. The evidence points in both directions.

The argument the Heat will fall back down to earth is simple enough to grasp.

Dwyane Wade will turn 33 in January and has battled with decline and various injuries in recent seasons. It’s unrealistic to think he’ll continue to play in every game for the Heat—he sat out 28 times in 2013-14—and less likely still to believe he’ll be able to continue his red-hot play. In his last five games, Wade has averaged 21.6 points on 58.1 percent shooting to go along with seven assists and four rebounds.

Bosh, meanwhile, has been playing like an MVP candidate in the early going for Miami, and it’s not unreasonable to expect some regression from the center.

According to Basketball-Reference.com, Bosh, through seven games, is averaging a career-high in points, steals and assists per 100 possessions and is posting his gaudiest rebounding marks since joining Miami. His .240 win shares per 48 minutes would be the best mark of his 12-year career.

No one should gird for a collapse from Wade and Bosh, but it’s possible that both are playing a little over their heads and are primed to return to their recent norms.

But, on the other side of the ledger, there’s also reason to believe the Heat will keep merrily marching along. It exists in the person of a big-ticket free-agent acquisition the Heat have barely been able to take out of the box.

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Miami has thrived despite a (very) limited Josh McRoberts, the power forward who came over from the Charlotte Hornets (nee Bobcats) this offseason. The Heat have been careful with McRoberts after he had an offseason toe surgery, but once they take the training wheels off, he should make for a perfect fit in Miami’s already potent offense.

It's a match made in hoops heaven. The Heat love to pass the ball, and McRoberts is one of the best passing big men in the NBA. They love to space defenses too, and McBob shot 36 percent from the three-point line in 2013-14.

It’s pretty clear his addition will help quite a bit, and help could be coming soon. The 27-year-old played a season-high 17 minutes against the Dallas Mavericks on Nov. 9 and appears ready to absorb a higher workload.

The Heat realistically don’t have the horsepower to win an NBA title this season. But with a healthy McRoberts, even with a bit of regression from the other parts of the roster, Miami could easily elbow its way toward the top of the Eastern Conference.

Fifty-plus wins and, say, a berth in the second round of the playoffs seems well within the team's reach. Sure, it's a bit of a dip from the title aspirations the Heat are accustomed to, but two weeks ago, outside of South Beach, that's a sunnier outlook than anyone could have expected.