But Bryant doesn't see it that way. He takes offense at predictions that he'll begin to decline at 32.
"You're telling me I only have two or three years left,'' he said when I approached him with the theory last week. "Tell me that. I want you to.''
In other words, he's happy to use the shrinking-window theory as inspiration to prove everyone wrong.
The issue of his longevity is hard to assess because the league is still trying to define players like Bryant, who jumped to the Lakers from high school as an 18-year-old in 1996. Does the league take his birth certificate at face value? Or is he viewed as being 32 or 33 in NBA years because he started his career so much earlier than the college-raised players of previous generations?
"Kobe's won three championships in a row from October to June, and that's a lot of basketball at a high level. So there is a lot of mileage,'' said Nets point guard Jason Kidd, who teamed with Bryant for USA Basketball in August. "But seeing him this summer and the way he takes care of himself, he's always preparing himself to play and be the focal point.
"It would be interesting if you compared his minutes. Don't look at the field goal attempts -- just the minutes, and that will be what it's all about.''
Taking Kidd's advice, I chose seven shooting guards and small forwards who rate above Bryant on the NBA's all-time scoring list and looked at how old they were when they had played roughly as many regular-season and postseason minutes as Bryant should amass by the end of this season (see chart, above right).
"It's silly,'' Bryant said of such comparisons. "It depends on the person.''
Of course, he's right. Bird had a far more brittle career than Bryant. Dantley was primarily a low-post player, while Miller was a catch-and-shoot scorer who played without the ball. The best comparison is with Jordan, but even that one was skewed by Jordan's "retirement'' from the Bulls for almost two years in the prime of his career.
I spoke with four executives from NBA teams, and three of them said they viewed Bryant as if he were actually a 31- or 32-year-old player because of his NBA mileage. But even if Bryant is more worn than the typical 29-year-old, one of the execs warned that he shouldn't be written off prematurely.
"Kobe is such a workout fiend, and there's nobody in our league as single-minded as he is,'' this team president said. "With his toughness and his mind-set, I would not put it past him to find a way to keep dominating for a long time.''
Then there was the one dissenting executive who cautioned against the entire theory, noting that there isn't enough data on players in Bryant's position to be able to draw a conclusion. This assistant GM believes -- as does Kobe -- that Bryant's NBA minutes may be far less relevant than his physical age.
Bryant has already adapted by becoming more of a perimeter threat, much as Jordan became over the latter half of his career. Jordan clinched his sixth championship with a jumper at age 35.
"Kobe could play at this level for a long time,'' Celtics coach Doc Rivers said. "Not only has he become a great jump shooter, but he's also developed that fadeaway [from the] post that Jordan developed. But it obviously depends on what's around him. If he has to carry the load, then that shortens his longevity.''
While Jordan was surrounded by positive energy, a negative -- and surely draining -- aura has enveloped Bryant in recent years.
"I just wish more people would celebrate Kobe, I really do,'' Rivers said. "Of all the guys in our league, that bugs me more than anything, that it just seems like we spend so much time trying to tear him apart and I think we're missing how great he is. And I think it's a shame.''
Bryant said he has relied more on his jumper because of the NBA's defensive rules -- and not because of his advancing age.
"The rules are completely different now,'' said Bryant, comparing his era to Jordan's. "I've always been able to shoot the ball, but the rules have changed since he played in terms of playing a zone defense. You have to be a jump shooter now because there's no way you can get to the basket -- particularly myself because they just stack guys up. I wish we had the rules they had back in the day where you could isolate guys and you could go to the basket anytime. But now you have to be able to shoot.''
The evolving science of athletic training should also enable Bryant to extend his career. Jordan took personal training to a new level by working year-round with Tim Grover. Now Bryant is raising the bar again.
"The techniques that we have available to ourselves now, the level of treatment that we have available is basically around the clock,'' Bryant said. "I have a solid team of five or six guys and women that are very capable in different areas: chiropractor, neuromuscular therapist, dietician, chef, yada, yada, yada.
"It's a lifestyle. If you want to continue to play at a high level, you have to make certain sacrifices. I mean, you can't have a burger every damn day.''
Bryant has learned to adjust his workouts over the years. "As you get older you get smarter, watch your diet, change your program a little bit. If you're willing to adapt, you can play for a long time.
"I work a lot smarter, more efficient, and it's not as taxing on your body. In the past it was just balls to the wall -- running and running and running and running, and jumping and plyometrics and all that stuff. If you're older, you don't need to do all that stuff. It's just about maintenance and injury prevention and staying in shape.''
Regarding Bryant's approach to the backstretch of his career, I don't think he's interested in winning just one more championship. I'm sure that he wants to win several of them. He wants to win more rings than Jordan's six and go down as one of the great players in the league. He was talking in those terms when I first met him a decade ago, and I would think his resolve has only strengthened since then.
So in that sense, the window is indeed shrinking. Say he is playing at as high a level as Jordan was at 35; that gives Bryant only seven seasons in which to win those four rings. If that's the way he's looking at it, then of course he's going to want the Lakers -- or another team -- to seize on his skills and exploit them to go for championships now, for their benefit as well as his. And the more talent he has around him, the longer he'll be able to extend his career at this level.
"I roll with it a little bit when they say there's a [two-to-three-year] window,'' Bryant said. "No way, no way. Barring injury or something like that, if you're willing to adapt, you can play for a long time.''
So how long can he play at his current level?
"I don't know,'' Bryant said. "We'll figure it out. I have a great staff of physical therapists and trainers, and we'll figure it out and work through it.''