For whatever it is worth, my goal was the same as JLV's - to have the track deteriorate and force you to take new lines. In SX that would've been jump faces getting rutted making them either risky to not cross rut or the lips getting depleted making it tougher to jump far enough to triple. For corners, they'd get acceleration chop exiting causing you to lose exit speed and bumps coming in causing you to have to come in slower or choose a new line.
For outdoors, it'd be rougher as you go in the main lines. Corner ruts would get choppy causing you to lose speed and move out of them or get long and deep enough that they were a challenge to stay in and it to be faster to switch lines.
The difficulty with this was and still is largely based around visibility more than the erode system itself as JLV provided quite a large number of options to tune the erode on our side. In order to make new lines, you need to be able to see them developing so they don't become a criss cross of chatter ruts before they can develop. In order to make realistic sized bumps that gradually get rough enough you start to avoid them without making it endurocross as guys like to call it, you have to be able to see them better.
There were plenty of other issues and wishes, but I still believe with a huge improvement in visibility it could be light years better with the system exactly how it is.
I will say, in theory the pre-rough tracks adding erode to them has always been something that's been tested and it does have some positives; however, it does 2 things negatively... 1) it neuters the theory of erode creating each race as an organic experience as the lines will always develop in the same places. 2) more often than not the erode actually smooths out the premade bumps and rails up the premade ruts making the main lines get faster versus slower as the race goes on. This isn't a unique problem as it's something I had to deal with all the way back to working on reflex.
The best erode system I ever played was a protype in development for Reflex and it was the most simple. The bike literally just "drew" a dark line into the displacement map with a higher opacity the more down force it was applying to the dirt. The more times you went over it, the deeper it got, but with any loading and unloading of the suspension it would still cause bumps. Jump faces would start to go away and you'd switch lines from it. It wasn't perfect either, but I haven't played anything in any game better than that. When that system was written to actually go into the game, it was also re-engineered to be more "real world physics correct" and the end result was way less appealing. A "map" was then created to erode down to for the final version where you could hide bumps and such that you'd uncover, but it was really just a hack because doing it physically properly wasn't working there either.
For those talking about it working better on the slower/smaller tracks. I think you're probably onto something. I also know JLV implemented some traction stuff that could've possibly opened a ton of new doors, but without any really good way to test and develop in a timely manner, it takes a ton of dedication from both a creator and the whole community.
It's not just an uphill battle, it's like smashing 5th gear head on into a cliff over and over. It's why I finally threw in the towel and from what I've seen it's why no one else has even attempted to put in much effort into making huge strides forward. I will never get those 200+ hours of my life back and it's really disappointing to see I never really was ever able to come up with something great. Sometimes, you just have to cut your losses.