For many of the reasons you indicated. Kids can simply load up on easy classes. I currently work with two members of the Byu admissions committee and until very recently, a close relative of mine was the Dean of Admissions at BYU. My interactions with them have made it clear that more and more, BYU is putting less emphasis on gpa and looking much more at other factors (standardized tests, difficulty of the high school curriculum, etc.). As a side note, the average ACT of the current freshman class is 28. The average ACT at Yale is 33, but they only have a student population of around 4000. If you take the top 4000 students at Byu from high school, the average ACT score jumps to 34. Pretty impressive for BYU.