I think it helps a lot that Meyer doesn't emphasize and stress talent, but effort. If a team's goal is to be the most talented, OSU has nothing left to work for. They've shown it, and they've convinced most of the country. Most of the time, complacency comes when talent and victory is the end game, because teams reach a place with those things where there's no longer much to build towards, because they've already arrived. Meyer preaches work and effort, every day. It's what Darron Lee was getting at, I think, when he said that he wasn't interested in hearing about the national title.
As for the "tough to repeat," line, I think complacency and loss of leadership are big factors in that. Case in point - when Chris Leak left Florida, everyone just sort of shrugged because, hey, Tebow is a pretty good QB. And Tebow was a great QB for them, 2006-2008. But in 2007, I think Tebow as LEADER was not yet the known commodity that it was by the end of his years at FLorida. Last year, Evan Spencer and Curtis Grant were not at the top in terms of any on the field statistics. But their leadership and how they carried themselves was emphasized over and over by Meyer as part of the reason for OSU's success, and that showed up big time against Bama, especially with Spencer. He made an incredible, near perfect throw to Thomas for the TD that changed the momentum of the game and set Bama reeling. He took out two LBs with one block to spring Elliott for the game winning TD. He snagged a tricky, perfectly executed on-side kick to avert disaster for the Buckeyes. On the stats sheet, it didn't amount to much, but it could be argued that Spencer was an MVP of that game.
Injuries could be a problem for us - especially up front on either side. At skill positions, our depth will absorb just about any loss. An interesting question would be which skill player on such a deep roster is the one that would be hardest to win without. My pick is Mike Thomas. His strength, speed, and hands as a receiver, and his experience and knack for making plays will be pretty crucial with Devin Smith gone. Yes, we still have Wilson, Marshall and others out there, but Thomas is kind of special, I think, and would leave a hole in the offense if injured. Zeke is incredible, but has good to great backups in Samuel and others. Obviously at QB, we're flush. On the other hand, the drop-off from our OL starters to back-ups would likely be troubling if an injury occurred. And on the DL, were Diesel or Bosa to be injured, the impact would certainly be felt.