The Yankees have been justifying A-Hole-Rod's contract by the fact that Texas has been paying part of the salary. IIRC, Texas is paying something like $6MM, so the Yanks are paying him approximate "Jeter money", or $19MM. Some of the money may also be deferred (I'm too lazy to look up details).
I wonder if Texas's "buydown" would continue to apply after the opt-in point. If not, the Yanks would be more likely to let him walk...