If you do fail, they'll make you go get a letter from your eye doc to certify that yes you're still able to drive. I always have to- I'm fine for driving just that I fail their stupid tiny symbols test every single time.
Oh yes.. I don't know about other DMVs but the one in SC will not accept out of state doctors' letters :P.
to y'all with your reading glasses lol. Bifocals since the age of 2 (and a really really really strong Rx), trifocals in my late 20s/early 30s thanks to the advent of computers. But at least my glasses are MUCH lighter and thinner because of the lens implants.
Ooh the "poof" eye pressure test... not a fan of those. Just had that done on Monday. Neither that nor the traditional one ever gets an accurate/true reading of my eye pressure... :P. But.. I still go at least once a year (right now every 4-6 months...)