yeah, man, not a good idea to wipe the inside of the lense, but oh well, we all have to do it eventually.  i have, and mine dont fog that often.  like its been said, leave them on your face, forehead is a bad place...  and if they fog because you are hot, just take them off and wave them in the air.  that, and skiing or riding a fast lift.  airflow solves most problems.  if they fog after a fall, try to get the insides as dry as you can. any snow or water will make them fog even easier.
-The Dr.-
Live for something, or you will die for nothing.
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