From a conversation I just had with a buddy. Couple things you can learn from the 14-time major champion.
1. It's possible to change the picture.
He's done it several times now and a couple of them have been pretty significant. You can look at a video of his swing and spot whether it was his "Haney swing" or his "Harmon swing". Here's my take on how he does it, he expects and is determined to feel "uncomfortable". He's talked about this in interviews and I've seen in person how he goes about practicing. So many golfers ditch new swing thoughts because it doesn't "feel good "to them when they should be looking to feel uncomfortable! Of course changing a piece in your swing doesn't feel normal, you're changing a motor pattern. It'd be like changing something in the way you walk, it's going to feel like crap until it starts to become your new normal.
Throughout the years we've all seen Tiger go through his slow rehearsals, on the range and on the course (especially after a bad shot). He "maps" out how he wants wants his body to move. Also, since he's hit thousands of balls with the old swing and to ingrain the new motion, he hits A LOT of balls forcing himself to do it the new way. I don't think every amateur has to hit thousands of balls but they'll probably have to make thousands of rehearsal/slow swings in order to see long term results. To make the change stick you're going to have to think about moving your body or a segment of your body in a specific way, you have to do it slowly and do it thousands of times. Seek out that uncomfortable feeling, because if it feels normal, you're not changing the picture.
2. Don't get caught up in a "style" of swing, focus on a priority.
I think it's pretty common knowledge that Tiger loves to tinker with his swing. I think Como has him more focused on the important stuff now but certainly in the past he has gotten too concerned with how he wanted his swing to look rather than focusing on making it more efficient. Butch was actually against making all the changes to get to his "2000 swing" but Tiger was able to talk him into it. He wanted a swing where every position was perfect. With Haney it was the same line of thinking, except the definition of what was perfect changed. He bought into Haney's single plane theory and started rolling his forearms to a great degree on the backswing and had the club laid off at A4. With Foley it was about trying to look more like Grant Waite. And when it comes down to it, the changes were more "style" oriented: arms plane, forearm rotation rates, elbow location, his pivot/body stuff hasn't changed a great deal.
Tiger is great at changing the picture but he's been changing it for the wrong reasons. It's based on the premise that if his swing looks "perfect" he won't hit bad shots. I think it's a good thing to always be working to improve but you can do that without rebuilding your golf swing over and over again. Rebuilding swings or starting from scratch is a complete waste of time and your natural tendencies tend to stay with you no matter what swing you adopt. Tiger has and will always have the head dip, it's just part of golf swing DNA.