I hate to resurrect this, but why do you guys clean your probes to begin with? I see wiping them off at the most, but not cleaning them. I mean, you don't pressure wash your smoker before every use right? Is it just an anal-retentive thing, or OCD, or am I just missing something? Does the brown/black discoloration wear out the probe faster somehow?
I think your experiment was pretty cool, but I just can't think of any reason the probes should ever get wet in the first place.
I think less is better as well. Plain steel wool to remove particles on the meat probe if not wiped right after pulling it from what ever you cooked works great and shines it up from smoke residue. No water necessary. If you must have it sterilized rub a cotton ball with rubbing alcohol on it, but I have never done that.