I was referring to the problem of Pac12 teams scheduling home-and-home series with other P5 schools and how USC seems to be the only one immune from that (I'll allow you to round up and consider ND's 5/8 status to count as a P5 team).
My bad. I misunderstood your point, but let's talk about that one for a second, because I disagree with it. Here's what everybody in the league has going as far as home and homes with other P5's that fbschedules.com has posted. I've excluded Stanford and USC's games with Notre Dame and any games anybody in the league will play with BYU:
Arizona-Texas Tech, Mississippi State, Kansas State, Virginia Tech, and Nebraska
ASU-Michigan State, Oklahoma State, Mississippi State, Texas A&M, LSU
Cal-Will finish up home and homes with North Carolina and Ole Miss in the next two years. TCU, Auburn
Colorado-TCU, Northwestern, 4 games with Nebraska, Georgia Tech, Kansas State
Oregon-Ohio State, Texas Tech, Baylor, Michigan State
Oregon State-Oklahoma State, Texas Tech
Stanford-4 games with Vanderbilt, TCU, they owe K-State a game in Manhattan, Boston College
UCLA-Oklahoma, Michigan, LSU, Georgia, Auburn, Wisconsin
USC-return game with Texas this year
Utah-Baylor
Washington-Michigan, Ohio State
WSU-Kansas, K-State, Wisconsin
Oregon State and Washington State will always have some trouble scheduling because of where they're located. Utah faces political pressure to play BYU (No, that isn't the same as our situation with CSU because the Power 5 leagues who have the one P5 opponent a year rule consider BYU a power 5 opponent).