<p>But conventional grades don’t have variance.</p>
<p>And I keep coming back to the original problem - which is that there is a disconnect between the accuracy of the assigned grades (which I acknowledge completely are inexact) and that of the GPA calculated from those grades, which is calculated to a precision not justified by the original assignment (and then used as a rigid threshold). </p>
<p>Although I concede your explanation for why that calculation is correct.</p>