[isoprophlex]

Yes, exactly this. Because it seems to be converging right now, I quickly get the feeling that there's no meaningful choice, after the first three prompts you end up with something that's neither green nor blue. Re-taking the test gave me a very different score.

It might work better for me to do some contrastive questioning: show a definite green followed by an intermediary color, then a definite blue followed by an intermediate color.

[wodenokoto]

The whole point of asserting where your border between green and blue is, is to ask about colors that are in between the two. It doesn't make sense to ask is RGB(0,0,255) blue to you? Well, unless you are color blind it is.

[isoprophlex]

Of course, that's clear as day; the idea is to reset your presumptions from the previous trial and sample the ambiguous colors in a more consistent way, by priming you from the extreme ends of the green/blue scale.

See it as a way to avoid perceptual hysteresis.