One of the things that has helped everyone, from donors to CDC to Sarkisian to coaching staff to Harris, is simply time. Most of the network and infrastructure is no longer unfamiliar. Yes, there have been a few new coaches, but that's about it. As folks are in the same roles for longer, they get better. Another factor, however, is that their flaws also become better understood and good managers are able to either help people work on those areas, or account for that weakness in some other way.
Last year and prior to that, Harris was not ready for prime time. He's allegedly in better shape these days, but I highly doubt he's some skilled guru that is in high demand on the open market. He's still somewhat inexperienced and immature and he's buoyed by literally the best resourced program in the world.
Sarkisian is something of a micromanager around the roster, so he's not going to be repeatedly surprised when the same shit rears its head with each big recruitment or position group. Kenny Baker's been here a year+ and that helps, but he also no longer has to beg for attention and resources at DT. He had to throw fits after watching the May/June debacle last year and that changed things there, as an example.
Most lessons aren't learned through success, in my experience. Overcoming failure and adversity leads to growth and experience, then hopefully success and wisdom. If you choose to learn at all. Tom Herman is a narcissist. He's been incapable of true growth and learning since the narcissism framed up his personality in puberty, most likely. Nothing is ever his fault, so what is there to learn? Sarkisian is the opposite of that. He's empathetic and introspective. That's almost to a fault, I think.
This is an introspective staff, led at the top by a guy who clearly is such. I'm just hoping that that finds its way into the red zone planning and playcalling this season. Allegedly the TE/A-back coach and Neal Brown are involved with just that, but we'll see.