I guess it depends on if he's absolutely amazing in the year before that happens and is completely injury free. In that case, a one or two year deal, sure, why not?
But right now, it'll be a basically risk free loan for a year for buttons, and if he's crap we'll say thanks but no thanks and be done with it. I have no clue why the option to buy is something to be aggrieved about.
To be fair I'm reading it as one of those definite buy-at-end-of-loan jobs which it may very well not be.