" It also asks those considering a ban to remember that later models of Glass allow for prescription lenses to be added and may be needed by people to actually see."
The actual wording is:
"Just bear in mind, would-be banners: Glass can be attached to prescription lenses, so requiring Glass to be turned off is probably a lot safer than insisting people stumble about blindly in a locker room."
Requiring that people use ordinary glasses if they need prescription lenses doesn't seem unreasonable to me, and is not the same as insisting people stumble around blindly. It doesn't seem unreasonable that someone using Glass with prescription lenses be expected to carry ordinary specs for just such occasions - or to just leave Glass at home and wear ordinary glasses when it's inappropriate to do so.
(And I am speaking as someone who does need prescription lenses - and usually carries more than one pair of glasses for different needs.)