When the crystal on your watch fogs over, the humidity inside the case is close to 100%! The moisture has condensed onto the crystal because it is the coolest surface. The case back is on your wrist, making it the warmest surface! Think about it! Turn the hairdryer on the watch and the moisture disperses away from what has become the warmest part, onto the dial, and steel parts! In my view, the hairdryer is NOT the way to go. If the crystal is removed, or the movement is removed from the case, the moisture disperses, never to touch the steel parts!