Rajon RondoRajon Rondo likes to tell reporters that he does a lot of behind-the-scenes work they never see. Apparently, there is at least one area in which the Boston Celtics are just as much in the dark.

Following a burgeoning trend within the NBA, Rondo employed a personal advanced-statistics guru this season, according to The New York Times. The Celtics point guard was one of a number of players who secured the services of Justin Zormelo, a 30-year-old Georgetown product who has also worked extensively for Kevin Durant.

“Before the game was over, he had everything broken down,” Rondo told the Times’ Scott Cacciola. “The text was already on my phone.”

The Celtics have their own analytics staff, including widely respected assistant general manager and team counsel Mike Zarren, but it appears the team was not aware of Rondo’s side work with Zormelo.

“Not really,” Rondo told the Times. “But I’m just trying to get better. There’s nothing wrong with that.”

Maybe there is, maybe there isn’t. Rondo is mistaken about one thing, though: It isn’t a simple matter of “trying to get better.” That’s not the premise of advanced stats.

Unlike taking extra jump shots or doing ballhandling drills, studying advanced stats doesn’t improve a particular skill. Analytics don’t teach how to play the game, but the ways to play the game that potentially maximize effectiveness. Even among analytics adherents, however, there is disagreement over what the numbers mean.

Perhaps Zormelo’s analysis of the data conflicts with the Celtics’. Coaches Brad Stevens and Doc Rivers, who each borrow from analytical concepts, had slightly differing philosophies on areas like offensive rebounding and mid-range jump shots, as shown in the varied ways the Celtics played the last two seasons. Those differences are fine as long as the entire team is running with the same mentality.

There are far worse ways for Rondo to be spending his personal time than analyzing his game, of course. Working with an outside stats analyst probably won’t cause Rondo to go rogue and start breaking from Stevens’ system whenever he pleases. But it is not as straightforward as one player “getting better” when the entire team is evaluating its own path to the same result.