True, but players also know that, and they collectively bargain for the idea that they don't get fully guaranteed contracts.
Like I said in another post... he got away with this because Bill O'Brien thinks he can coach his way to greatness and doesn't need to keep talent. A smarter GM would have told Hopkins to pound sand, and his options would have been play and get paid, or sit and not get paid. There wouldn't have been a trade or any extension given.
And as I said earlier already... if you know the day you sign the deal that you're going to be unhappy with the deal 50% of the way through, don't sign the deal. I think you're seeing that trend of players desiring like 2,3,4 year deals more often, because they're realizing, what's the point? What's the point of a 5-6 year contract when one of the two sides is likely to be unhappy with it after year 2 or 3? Ownership is in a win/win situation with longer contract structures. If the player plays great, they'll likely have him for cheaper on the back end. If he plays poorly, the can cut him and not have to worry about it.
So if the players want to maximize their leverage, shorten the deal. If the team is only willing to give you $40M guaranteed, why are you signing an $70M total contract?
Maybe teams won't like that, but I'd like to see the players make more of an effort to do it. The really good players generally have no problems getting 2 or even 3 years guaranteed on a deal. So why aren't you just signing a 2-3 year deal then? Fans say the "fully guaranteed" contracts can't happen. I think for 5-6 years, absolutely not. I think for 2-3 years, teams would be super willing to do it.