He's got his first round money, so Crochet's still set. I could see the deal somebody suggested above, 3/50, or something, lock in the arbitration money, give a little back for the first year of FA, then walk. But that's so short, why would the Sox do it?
And, as somebody else asked, why would the Sox encumber a trade with guaranteed money? Guys like Vaughn and Crochet are cheap and low-risk. If they s%*# the bed, non-tender them. Give the option of extending to the trading team.