Show 100 people, who do not suffer from color-blindness, either an example of blue or an example of green and they likely will be able to identify the color correctly. Show the same 100 people a card starting with blue on the left side and morphing to green on the right. Ask them to pinpoint exactly where blue becomes green and you will get many different answers. The answers will be skewed by subjectivity. The extra grade options will offer the same results.
