I am not a doctor, but if true, that sounds completely consistent with this hypothesis (deoxygenated blood is darker, and being able to breathe won't help if yo

I am not a doctor, but if true, that sounds completely consistent with this hypothesis (deoxygenated blood is darker, and being able to breathe won't help if your hemoglobin can't carry oxygen) I would be fascinated to hear their take on this article.