I had glaucoma surgery last year and can no longer wear soft contacts.
I went to Smith Turbo (2 speed fan w/Battery pack) and the Smith Ocular Docking system. I use a very powerful antifog treatment on the insert lenses called FogTech. I ski in a Race style helmet which excerbates the fogging problem, even though my helmet has a vent. It does not have a lot of airflow.
The Fan (low speed can be left on all day & you use the high speed when you slow down or get in the lift line to keep them clear) along with the FogTech (available on-line & REI) that I would reaaply lunch worked pretty darn well!
FogTech comes in individual packaged wipes so you can throw a couple of those in your pocket and reapply at lunch. You only need to do the insert lenses since the inside of the goggle lense itself does not fog up and is permanently anti fog coated.
This sytem worked very well once I got the anti fog product figured out. If he wears a more ventilated helmet like a Giro Fuse that would probably help th fog problem immensely.
I am working on breaking my eyes into hard gas permeable lenses so I can go back to me Briko Icarus goggles! But it is a slow process for me!
Wearing glasses under my goggles is not an option, they are progressive bifocals and i did not want to go that route.
another solution which i use on sunny days are panoptx prescription sunglasses with removable eye ups that seal around you eyes. The eycups have a separate lenses from the glasses frame and can be permantly anti fog coated. I got Scirroco frame. Check 'em out!www.panoptx.com