"Exactly wrong"

[Beebop]

From: Altitude and Mortality

There are some popular medical ideas that obstruct clear thinking about respiration. One is that high altitude deprives you of oxygen, and is likely to be bad for people with heart disease and cancer. Another is that breathing pure oxygen helps sick people to oxygenate their tissues while exerting less effort in breathing. These are both exactly wrong, and the errors have been explored in quite a few publications, but the ideas persist in the culture to such a degree that our perceptions and intuitions have been misled, making closely related things seem to be unrelated.

From: Gelatin, Stress, Longevity

(Again, the popular nutritional idea of amino acids as simply building blocks for tissues is exactly wrong--muscle protein can exacerbate muscle disease.)

Bolds are mine.