exciting. Growing up, it was all about watching UCLA play; and banter between my dad and his buddy who was a USC grad was always fun to watch. We'd go to his house some years to watch the SC/UCLA game, and some years he'd come to ours.
Stanford and Cal were always big games for us; but back then, we really didn't care much for the other teams.
The fact that they added Utah and Colorado made no sense to people who grew up in P10 country; even the addition of the AZ schools wasn't a huge "get" for us at the time. What matters in P10 country was the core California schools, and then the Rose Bowl game, that was ALWAYS against a B10 opponent. THAT history was what meant something to P10 fans.
With the expansion of everything, the P12 completely lost out. Larry Scott went after Colorado to try and force TX and OK to join, and it backfired; so now he has a bottom dweller team in Colorado and needed someone to pair up with it. While BYU from a business/strength point of view is your obvious choice, the anti-religion group that is the P10 core just wouldn't let that happen, so they settled on Utah.
While other conferences like the SEC got stronger with expansion, the P12 got weaker; THAT is their problem, their product got greatly diluted, not even stayed at the same level by adding people.