I teach at BYU and have been in a student ward bishopric. Don't kid yourself, this is how it works. The overwhelming majority of offenders (including the two that got pregnant out of wedlock in my ward and their boyfriend in one case and just friend in the other case) all stayed at BYU because they were repentant. My experience was that the only ones that had issues with the HC office were those that were repeat offenders (for serious, serious sins not pornography or other serious, but not serious serious sins), not repentant, or were high profile people representing the university.