Right-- the point is that it isn't good for any students to be too far from the center of the distribution relative to a peer setting.
But this ignores the mathematical reality that someone has to be on the edges.
It also ignores the reality that there is a pretty hard delineation in terms of "gap" there-- that is, exposure to people half a standard deviation beyond yourself in ability is GOOD, and encouraging since you can practice full cognitive extension/reach regularly, but placement with those TWO standard deviations beyond your current ability is highly detrimental and damaging.
It's the second part of that which seems to have completely eluded most educators, I have found. That boggles my mind.
This is why students are retained. Sheesh.
