I think CES explicitly accepts the broad objective of improving social mobility, and would accept the somewhat narrow measurement of this specific social mobility score as a legitimate metric. I'm sure their method of addressing social mobility across the worldwide church includes different missions assigned to BYU, BYU-I, BYU-H, LDS Business College, independent study options and even the Perpetual Education fund. They wouldn't be surprised to find that BYU scores low in this study because that isn't the mission assigned to BYU. It would be interesting to see how BYU, BYU-I and BYU-H scored as a collective group.