data. A student that just "shows up" for a semester can have a huge negative impact when only a handful of students are enrolled each year. If just one out of 10 students drops out, you're dropped a key stat by 10%.
It's always been my view that this was all a bunch of premature hand-wringing and I still believe that's the case. I doubt BYU would have gone after him if they weren't fairly confident he could be admitted in some program. Just like anything, there may be details they hadn't counted on being an issue. In looking at things more closely, I can see how it may get complicated.