This reminds me a bit of when we signed Deschamps (I'm not saying they are alike as players, just his age, experience, etc).
In those days we needed a DD to add World/European class to the midfield (even if it was for just one year), but we are a very different club now, and should be looking to the future.
For me, it all depends on the cost. If he was going free, then I'd be all for it, but with a large transfer fee (as looks likely) I personally don't think it's a gamble worth taking.