Sorry to dig this up, but what is the lowest temperature Rodinal is effective at?

I was thinking of doing some wacky stand development with high dilutions in the fridge for a few hours or a day. Tell me would this work? and do you think it would have the benefit of reducing the grain size?

I would love the convenience that I could toss it into the fridge, go to work, come back and its all done! haha or maybe I'm dreaming. Or maybe its the lack of sleep thats making me think these crazy things.