I don't think he fully understands the form factor of Google Glass - from the way he describes it as his "generation one" it seems as if he's thinking of it as

I don't think he fully understands the form factor of Google Glass - from the way he describes it as his "generation one" it seems as if he's thinking of it as a vision replacement like his glasses. Actually they're a small screen in the top-right of your vision which you don't look through, so these negative effects wouldn't apply.