By the time I was involved with the D1 event (I started in '87), the main determination for the number of qualifiers per conference was the collective conference team score. Apparently, the Southern and SEC had waned considerably by then. The committee asked me to do the conference team score calculations and give my conclusions. The algorithm was simply (total conference score / total tournament score) * 330. IIRC, D2, D3 were always 20 and 10. I assume that by conclusions they weren't looking for wise-ass but wanted the number of qualifiers. But I decided to use this one as a loophole. As it turned out one of the conferences "earned" 0.6 qualifiers and the other 0.4. So in conclusion I suggested merging the conference and qualifying only the OW.
They didn't use my conclusion.