Re: 20/20 ... AVG -- Won't happen
20/20 is purely a measure of one's ability to identify letters in a certain typeface and of a certain size from a distance of twenty feet.
> You might have written "many people have ..."
I might have, but I didn't. What I wrote was less vague and just as accurate. The average person does have better than 20/20 vision:
...both Snellen and Donders noted that acuity levels of better than 20/20 were common in normal individuals, and both cautioned against a conclusion that their norm values represented normal visual acuity. Unfortunately, these cautioning remarks have rarely been heeded..."
- http://link.springer.com/article/10.1007%2FBF00413146#page-1
he significance of the 20/20 standard can best be thought of as the lower limit of normal or as a screening cutoff. When used as a screening test subjects that reach this level need no further investigation, even though the average visual acuity of healthy eyes is 20/16 to 20/12.
http://en.wikipedia.org/wiki/Visual_acuity#Normal_vision