Riverboat gambler or game-changer? Undersized blue-liner or gifted defender? And, most pressingly, Norris Trophy favourite or just finalist?
The last question remains top of mind for members of the Professional Hockey Writers' Association as they prepare to cast their ballots at the conclusion of the regular season. The fact the 21-year-old Ottawa Senators defenceman is even at the centre of the conversation speaks volumes about how far he's come.
"It's certainly probably as quick a rise as anybody in a long time," Senators general manager Bryan Murray said this week in an interview. "We'd like to see him rewarded."
Karlsson's case seems to hinge on whether his dominant offensive numbers are enough to vault him past the NHL's "Big Three on D" — Nashville's Shea Weber, Boston's Zdeno Chara and Detroit's Nicklas Lidstrom — who are seen as being much more valuable defensively.
By its definition, the Norris Trophy aims to recognize the defenceman "who demonstrates throughout the season the greatest all-round ability in the position."
Murray believes some of the criticism of Karlsson's defensive play stems from his first two seasons in the league, when he took more chances and was a combined minus-35. As a result, he earned a reputation that hasn't been easy to shake despite turning into a plus player.
"This is really what kind of is interesting to me — he plays now as a matchup pair," said Murray. "Him and (Filip) Kuba quite often are the one that gets the good line on the other team. His mobility, his stick positioning, his strength and his ability to get in body position are so much improved.
"I don't think he gets nearly enough credit for this."
Discussions about Karlsson's candidacy inevitably drift to the things he doesn't do, such as killing penalties. All of Ottawa's defencemen see more short-handed time per game than Karlsson — as do Weber, Chara and Lidstrom.
But the wispy Swede has been the most dominant among blue-liners at the other end of the ice by a significant margin, carrying a 24-point advantage over Florida's Brian Campbell. With 71 points in 71 games, Karlsson was on pace to become the first defenceman to go over the 80-point mark since the lockout.
Hall of Fame defenceman Denis Potvin has had the opportunity to closely chart Karlsson's progress while working as a TV analyst on Sens broadcasts the past two seasons. Even he is somewhat conflicted.
On one hand, he notes the lack of physical play from the six-foot, 180-pounder — "I don't think he'll hit anybody," said Potvin — but on the other he marvels at Karlsson's ability to control the play.
"The improvement he has made in one year is phenomenal," said Potvin. "I don't know that I've ever seen a young player go from 20 years to 21 and make such an improvement. Because he wasn't very good at 20 and that's part of it. (He made) poor decisions, didn't seem to be very strong, but had obvious skill.
"This year it just seems like he gained so much strength, first of all, and then the poise that now he makes the smarter plays."
The Norris Trophy debate has been raging on blogs over the last couple weeks and will only intensify as the regular season winds down.
Many feel that Weber is overdue to win the award. A year ago, the Predators captain finished second in voting to Lidstrom, a seven-time winner, and he's put together another strong year for a team that has Stanley Cup aspirations.
Barring something unforeseen, Weber and Karlsson should be among the three finalists.
An interesting subtext to the discussion is the fact Karlsson is playing out the final year of his entry-level contract. He's set to become a restricted free agent during a summer of uncertainty that will see discussions begin on a new collective bargaining agreement.
Meanwhile, Murray says he's only had casual conversations with Karlsson's agent, Craig Oster of Newport Sports, and isn't yet sure if the sides will attempt to negotiate a short-term or long-term deal.
The fact this has been such a breakout season for the former first-round pick could complicate negotiations.
"I think we've seen young players get huge contracts and not play as well afterwards," said Murray. "So we have to talk about sort of a plan going forward, whether we go long term or short term. My philosophy has always been that you never want to underpay a play — you want to reward him — but you don't want to overpay to a point where you're upset about the contract afterwards."
Of course, that would only happen if Karlsson ends up having a severe dropoff. It's hard to imagine that happening with the strides he's made in just three NHL seasons.
Whether Karlsson wins the Norris Trophy this season or not, he could be part of the debate for years to come.
"I do think that this is not an anomaly," said Potvin. "He's going to be in contention for a long time."