If you cold steep the dark grains, I don't think you'll get as much coffee flavor/aroma. A friend of mine did this and just added the liquid at the end of the boil and it produces a smoother roastiness that doesn't overpower the beer.
Without question, the greatest invention in the history of mankind is beer. Oh, I grant you that the wheel was also a fine invention, but the wheel does not go nearly as well with pizza.
- Dave Barry