At least if you believe this site:
That said, I don't know if BYU's record ATS is statisically significantly different than .500, though I'd assume a .525 record ATS is pretty good.
Interestingly, BYU is .500 ATS as a home favorite since 2003 and .448 ATS as a road favorite. So overall, BYU is not good at beating expectations as a favorite (.482).