First of all, don't go by overall rating. Overall rating is best for determining how much a player will ask for in free agency or arbitration. But in determining how good a player is, look at individual ratings.
Second, just because a player is performing poorly now doesn't mean he's a bad overall player; maybe you should post the ratings of both players and we can see whether the deal is truly so one-sided.
That said, sometimes owners do propose deals like this because other owners are willing to do them. I've proposed similar deals to guys with dozens of seasons of experience and had them accept for reasons that are beyond me; it's just called getting the better end of a deal. As your other owner said, can't hurt to try...