Why is it silly? You can call it a terrible move in hindsight if, say, Raanta posts numbers as bad as Smith's or Tellqvist's or someone like that, but hindsight won't come until the end of the season. For RIGHT NOW, it's not just a good move, but a GREAT move, because either a) we have a goaltender of the future or b) and easily-escapable failed short term gamble. We're not locked up for a couple more years with a declining asset in Smith, and we haven't spent a ransom in dollars or term for one of the UFA goalies out there (which, I'm sure you'd agree, is a tremendously underwhelming group of players).
From an asset management standpoint, the deal for Raanta is about as good as it gets - a low-risk, high-potential-reward situation that doesn't hamstring the organization in any significant way.