As far as trends go opening games may not fit the bill in all cases. Looks at Texas. In the past 10 years The Longhorns won those 10 games by any average of 36.8 points. No trend there that applies to playing a top 25 team. Those 10 opponents included North Texas (twice), New Mexico St, Wyoming, Rice (twice), ULM. FAU, Ark St (score was 20-13), and La Laf. So trends are what they are but not all situations fit the bill. I do not see Texas beating ND by 36 points, ain't happening lol.
Another thing about trends in general. You have to consider who the present HC is and how he fits trends that existed at his current school before his arrival.