I thought I knew how beneficial it would be and I thought I knew what I wanted to get out of it. I was kinda wrong on both counts. The personal consultant approach makes the leap between L3 and L4 huge.
Take what we all know about CSS coaches. They're well versed in the hangups regular humans have in riding motorcycles fast and they're incredibly skilled at breaking down those barriers and knowing what the riders need to become better. Now, take those skills and remove the confines of teaching 5 new skills in a day and just let them have the time to fix whatever needs fixing and that's the difference between L3 and L4.
I was at SoW. I was struggling at the kink and it turned out the problem was actually starting at the turn-in for 8. This was nice but the next revelation was that I was turning too slowly. It never felt like it to me because I was able to hit my marks at the speed I was riding. But much like the previous issue, the solution was not what I expected. I thought once I had more pace, I'd turn more quickly. But once they got me to really turn more quickly, I found that I had to up my pace. Again, the solution to a known problem was far from intuitive. After circling SoW who knows how many times at basically the same pace (better form each time but never more pace), being forced to do quick-turn correctly (in my case, push-pull) forced me to approach the corners with more pace because if had turned more quickly at the same entrance speed, of course, I would have early apexed. This one change got me 9 seconds.
Next year I'm going to find a stretch of 3 or 4 days at SoW and book multiple days at once. Primary focus (I think) will be T1. Can't wait.