Gotcha - now I understand. Thanks. One final question: what is the stuff about fusional reserve? I think I understand that it's to do with the ability to bring the eye back in, is there any way to tell whether I have 'sufficient' fusional reserve?
OK, really the last question: the JAA regs talk about usual correction, does this mean I can get glasses to correct it, or is it just saying that if I do wear glasses for other stuff then they've got to be on when it's measured?
And that was the last question.
Promise.
For now!