Here is the issue and keep in mind that 20% of the cap can be allocated to a single player.
Say Crosby was up for free agency, he can make $12M/year on a 5 year deal. Let's say he takes $8.7M/year as he currently does on average.
Now let's say David Backes is up for renewal. On a 5 year deal, how much do you think he'll make? He's on $4.5M now, so $6M a season? What about Richards? $7-8M? These owners will pay them higher salaries per year to make up for the term and to get them away from other teams. And the 5% variance will ensure that if a player makes a high salary in one year of a contract, he has to be paid a high salary over each year of the contract. Just like the owners are now, they'll do whatever they can to sign the player. That's exactly what's happening in the NBA because owners are overpaying players in this sort of model.
Economics will tell you that, as teams do this, players will naturally be grouped into the higher pay bracket. As this happens more as the years go on, this'll happen with all teams. Then players that should be making $2-3M a season will make closer to $1M if since teams have no restriction on how many players in high pay brackets they can fit on a team.
That's how the middle class of the player is being destroyed in the NHL's proposal.
Now I understand the issue. But the combination of the 5% variance and a max contract length destroys the league. I was a proponent for the variance before as a substitute for max contract lengths, but both together doesn't work.
Now if they wanted a 5-year max length with say a 20% variance, that gives an owner more flexibility to not necessarily have to pay a player $6M or thereabouts every season during the 5 year contract. The owners have to either choose one: 5% variance with no contract length so they can offer a lower per year salary over a longer time, or a max contract length with a higher variance to provide flexibility in per year allowable salary.
You have to understand the problem. Don't just blame the players because you think they're greedy. The economics of the sport affects your entire experience as a fan.
Does that make sense?