Blake will defenitly not be worth the money he will be getting.
I've been a big Jason Blake fan for half a decade now, or not a fan, but you know like acknowledged what he brings to the game.
But, after posting good numbers he will be payed the same amount as guys who can post thoose numbers in any enviorment, Blake can't do that. He is like Straka, always valuble for his team, but wheter he is a 50 or 80 pts players depends on who he is playing with, and how his team plays, what style ect. Paying him 4+m per season he will have to be a very important part for your team.
I think there is a big risk building a team around players like Blake, even if you only see him as a building block on a 2nd line. He doesn't have the hockey sense to create things for his line on a regular basis, the result might be that you get a team that runs into a wall flat if you only rely on players that needs to be in certain kinds of situations to succed.