I have been seeing the same optometrist since I first got contact lenses when I was 14. So, he knows my eyes. He knows that I'm quite blind without corrective lenses. Yet, every couple years the staff has to get funny.
First they check my vision with my contacts in. They use the usual chart. I'm usually in the 20/20 range. Then they ask me to take out my contacts (to do other tests). I put on my glasses, and they check my vision with my glasses.
Today the assistant had me remove my glasses and read the chart.
At the top of the chart is a large E. I know this. Unfortunately, I can't see this without the help of glasses or contacts. The top of the chart is graded to be read by someone with 20/200 vision. My vision is more in the range of 20/700.
What I can see is where I should be looking. I see the light. And if I squint just right, I can sort of, kind of see a couple horizontal stripes, but they're very indistinct. When the assistant asked me to read the chart, I laughed. "There's an E there someplace," I said.
She quickly realized the futility of that exercise, and she let me put my glasses back on.