One of the problems we see with the arbitration system is that it constantly drives up salaries for individual players regardless (almost) of performance. Texas couldn't account for the risk of another down season by offereing the same pay - or a cut - so is essentially forced to trade him. Even if Texas thought a bounce-back likely, the process of one-or-the-other outcome means the player's agent can argue that the team EXPECTS a bounce-back by the fact they DIDN'T trade him, and if the team bids low to cover the contingency that he doesn't fully bounce-back, they lose and are stuck with a less-desirable contract, which gets them less in the trade.
So, the system perversely makes it almost necessary to trade a player who doesn't have a stellar season, because the cost of losing in arbitration continually drives the payroll upward for players who may never improve. More and more, true free agency makes more and more sense for the 3-7 year players.