Hi I'm blind as a bat without specs so my prescription Racing Jackets are pretty important when I'm mountain biking. Despite having vented lenses they continually fog especially at this time of year or when it's raining. I've tried all the usual - spit, washing up liquid, polish and more recently Fogtech DX but nothing works. Any other suggestions? Ya and sorry if this has been asked before. I did a search for fogging but couldn't find anything relevant.