But to play devil's advocate here for a second, if Crosby ever did this, I'm not sure if the NHL would be ready for the results. Crosby is the poster boy for the NHL who signs in the KHL. That should speak volumes of what shape the NHL is in.
Then again, if it helps to get rid of Bettman, maybe it'll be a good idea
It's about as likely as me winning the lottery and then donating it all to charity.
Honestly...this is much less likely.
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“The most terrifying fact about the universe is not that it is hostile, but that it is indifferent. If we can come to terms with this indifference and accept the challenges of life within the boundaries of death, our existence as a species can have genuine meaning and fulfillment. However vast the darkness, we must supply our own light.” - Stanley Kubrick
If I were him that's what I would do given the injury history. Might as well make 4-5x the money in a less headshotty league rather than sign here and get run by everybody. 20 million in the KHL vs 5 million after taxes and escrow + a retirement inducing concussion in the NHL. Not that hard of a choice.
The bulk of Sidney Crosby's income does not come from playing hockey, it comes from endorsements.
I actually think it would be a good idea for him to do that. I think it might be for the best considering that he will be playing in the league that is far less physical. It would give him a chance to fully heal while keeping his conditioning at the top level and all of that while making more money. (Though, the money thing is a speculation given that I have no clue on what he makes off of his endorsements.) To answe the OPs question however, well... Another poster summed it up nicely with the whole lottery comparison.
I would absolutely do that if I was him. Twice the money to play in what is for all intents and purposes a no contact league? he's making like what, 5 million after taxes? he would get 10 million tax free over there, easily. The NHL still doesn't have it together regarding head shots and the like, and even if they did that league will always be too physical because of the tiny rinks. Sid could chil-lax with pond hockey and make sick bank. If he truly cared about himself, he would do this.
Yes, I know that the KHL offers big money to borderline-NHLers, AHL star players or European players to play in a less headshotty league, playing 54 or 56 games a season.
Plus if a KHL team offered $25M/season, they're basically eating up nearly all their cap space on Crosby. So, unless there is some clause in the KHL CBA that would limit how much cap space to spend on one player (even if that player is a designated player) the GM doing that would handcuff his team for 3 years.