This is something I've been wrestling with as well. Ever since I started reading these boards I've read the 'buy low, sell high' mantra too many times to count. Isn't Karlsson the ultimate sell high? He won the Norris as a 22 year old which, as far as I can tell, hasn't been done since Bobby Orr won his first one in 1968. He isn't leaning on superstars like Ovechkin and Backstrom to score his points, he's doing it all himself. The last defenseman to score 78+ points was Lidstrom (80 pts) in 05-06, although Green has come close twice since. He has played 217 games since his first season in 08-09, only missing 13 games due to injury, so he's durable. I am hard pressed to find a negative thing about him at this point. For his first two years the knock against him was a truly awful +/- (which is the only reason I was able to get him in the first place), but last year he was +16.
The fact that there's nothing bad to say about him is both a good thing and a bad thing. It's a good thing for you, the owner, because you've got this great piece that everybody wants and they have almost no flaws to gravitate towards to make you doubt his value. It's a bad thing because of 'buy low, sell high.' Who wants to buy someone at the absolute height of the market, when the only way to go is down? It'd be much easier for the other GM to wait for Karlsson to stumble a bit so that he has a bit of leverage in talks.
It's incredibly frustrating and I've decided to just hold onto him and enjoy his ridiculous numbers. Trying to get another owner to realize that packaging him with a 90 point forward to land Malkin or Crosby just isn't worth it is exhausting. Likewise, trying to convince another GM that Karlsson is worth more than an 80 point forward is equally tiring.
16 team, full keeper
19 roster players, 15 prospects
Stats: G, A, PPG, SHG, special teams assists, SOG, FOW, PIM, hits, blocked shots, +/-, W, SO, saves, s%, GAA, shootout saves
C: Crosby, H. Sedin, Boyle, Brassard
W: P. Kane, Voracek, Burrows, Ott, Filppula, Dorsett, Hudler, Bouchard, Zuccarello, Stalberg
D: Karlsson, Letang, Enstrom, Boyle, Giordano, Gorges, M. Stuart
G: Quick, Bryzgalov, Kiprusoff, Ellis
Prospects: Granlund, Atkinson, Pirri, Killorn, T. Johnson, Galiev, Corrado, Koekkoek, Moore, Rundblad, Bachman, C. Johnson, Desjardins