No one is doubting Allen's ability as a long range commodity. He is the NBA's all-time leading three-point shooter who knocked down a staggering 45.3 percent of his attempts only last season.
What we have come to doubt, though, is Allen's ability to do anything else. He has never been a lockdown perimeter defender and we can hardly envision him attacking the rim or pulling up off the dribble.
Because, after all, he's a spot-up shooter, reliant upon top-tier point guards like Rajon Rondo who can create space and scoring opportunities.
Except, that's not true. Allen was, and remains, more than a spot-up shooter, more than a one-dimensional scorer, more than merely a bit role player.
And somewhere along the lines, somewhere during his five-year stint in Boston, we forgot that.
But we won't be able to ignore it any longer, not since he has joined the Heat. Though the move was—and still is—considered a largely controversial decision, one that has been debated and scrutinized to no end, Miami presented Allen with an opportunity, with a perspective that the Celtics simply couldn't or didn't.
I'm not referring to the ability to contend for a title, because Boston, in all their elderly glory, still has what it takes to do that, even without Allen.
No, I'm simply acknowledging that the Heat acknowledged what the Celtics would not—Allen's value inside the three-point arc.
Once he latched onto the Heat, Allen's role was clear: he would become an instant sideshow to the center stage act that was the Big Three, camping out beyond the three-point line and capitalizing off of LeBron James and Dwyane Wade's penetration kicks.
And you know what? That's exactly what he's going to do. But it's not all he's going to do, as Shandel Richardson of the Sun Sentinel reports:
The Heat will explore options to prevent Allen from being solely a three-point threat. Heat coach Erik Spoelstra said they will use Allen in a variety of ways. His role has yet to be defined as the Heat staff continues to brainstorm how to utilize their prize offseason acquisition.
At the moment, Allen has no concerns about shooting 26 percent from the arc in the preseason. He says he's more worried about other areas of his game.
"I can still put the ball on the floor, go to hole, make the pass," Allen said. "I shoot threes but I try to get to the hoop as much as I can."
No, surely Allen jests. He can do more than simply spot-up and pull the trigger? That's simply not true.
Except that Allen himself, the facts and reality tell us otherwise.
Prior to joining the Celtics, during the 2006-07 campaign, Allen's last season with the Seattle Supersonics, he shot just 37.2 percent from behind the three-point line, the third worst mark of his career. In the interest of full disclosure, he was also jacking up eight attempts per game, yet even so, just three of them were put through a night.
But that was still the best point-tallying season of his career. He averaged 26.4 points on 43.8 percent shooting per game.
How? Because he was allowed to operate outside the confines of the rainbow by going to work within it. That year he attempted, on average, 12.8 shots per contest inside the three-point line, a third of which came at the rim, where he converted on 61 percent of his attempts.
So, before Boston, before Rondo and all that jazz, nearly 61 percent of his total offense came inside the three-point line, and nearly 20 percent of his total clip came at the rim.
By comparison, in Allen's last season with the Celtics, roughly 48 percent of his shot attempts came from downtown, 69 percent of his total offense came further than 16 feet away from the basket and less than 16 percent of his scoring opportunities originated at the rim.
Yes, Allen was taking less shots, but in the process, his creativity was being stifled as well; there wasn't room for the self-sufficient Allen in Boston, especially last year.
But there is in Miami.
The Heat are an exceptionally deep team, yet while both James and Wade prefer to operate with the ball in their hands, neither is the ball-dominator Rondo is. Which is exactly the type of free-flowing dynamic Allen needs to regain his star status.
Bear in mind, Allen also averaged over four assists per game before heading to Boston. During his time with the Celtics, though, his average dipped to 2.7. That's a significant drop, especially for an athlete who dished out 5.9 dimes per game during the 2002-03 campaign.
But that drop is telling, and subsequently critical to Allen's evolution in Miami.
Because what this essentially tells us is not only did Allen have the ball in his hands much less, but he wasn't given the freedom to create as much.
This comes back to Rondo to an extent, but it's not solely on him. He's a point guard and it's his job to have the ball in his hands.
Yet at the same time, it is a testament to the restrictions set in place for Allen, whose usage rate dropped 29.51 from when he left the Sonics to 18.59 by the time he left Celtics.
And while it would be easy for us to attribute this to age and injuries, Allen's offensive efficiency hasn't suffered—he shot nearly 50 percent from the field in 2010-11—and until last season, he had missed just 16 regular season games over the past four seasons, a rate of play Wade himself could only dream about.
Which means it goes beyond his age, beyond the injury-riddled campaign he suffered through last season and into the unsettling reality that the Celtics just weren't the best fit for him.
Yes, he won a title in Boston and came within one victory of a second. And yes, he was selected to three All-Star games, but his offensive creativity was also asphyxiated well beyond the rate of natural regression.
And even worse, it wasn't acknowledged. The Celtics continued to mold him into a one-trick offensive pony, which culminated in his demotion to a bench-role by the end of last season.
That's where the Heat differ. Allen will come off the bench, but he will enter the game to an offensive dynamic that knows it has more than a spot-up shooter in him, that is willing to utilize what is actually a broad offensive skill-set.
Allen's subtle demise has never been about age or his inability to produce. In fact, the numbers tell a different story entirely. When he's been able to shoot, he's made the most of it, he's remained efficient. And when he was given freedom to roam with the ball in Seattle, he exuded a willingness and ability to create for those around him.
But he wasn't given that freedom under Doc Rivers, alongside Rondo, as a member of the Celtics. He is what we believe he is today because that's what Boston's system made him, or ostensibly made him, because that's not what he really is.
Which is why Miami doesn't need to implement any complicated offensive schemes to tap into Allen's vast potential. They just need to allow him the freedom to be the player he actually is—an obnoxiously lethal shooter with the ability to attack the rim, create his own shots and even help his teammates' offensive cause.
The Heat are going to allow Allen the freedom the Celtics never did, encourage him to be the versatile scorer he always has been, the one Boston made everyone forget about.
They're going to give him the opportunity to reclaim his rightful place amongst the Association's superstars.
"I don't know what this dude does but I need to take some tips from him," now teammate Chris Bosh said thinking back to the 2011 playoffs when the shooting guard posterized him.
Now, finally free from the shackles that became Boston's offensive blueprint, Bosh, and the rest of us, we'll no longer be left to wonder what it is Allen actually "does."