I found this recent comment interesting, as one of the most frustrating aspects of healing bad knees is getting the "Goldilocks principle" right: You don't want to move too much. But you don't want to move too little either.
I find your book useful as you say that during your initial months, you were not sure if you were improving or not and it was by month 7 that you knew your plan was working.
So you need to move your knees. To me, that's like a First Principle, not open for debate. Knees that don't move at all will only get worse.
But then how much do you move them if they hurt all the time/most of the time/some of the time? And how can you tell you're on the right track with your program?
This is very, very hard to do. It's where many people fail, I'm sure. There is no "Just do this" blueprint. Just imagine how easy healing would be if the prescription was something like, "Take 800 steps a day for the first four weeks, then increase that by 200 steps a day for the next four weeks, etc."
The problem is, that may be just right for your knees. Or too much. Or too little. Or your best approach to healing may not be through walking at all.
There can be a lot of experimentation during those first few months that feels more like flailing around. It's important not to push your knees too hard. But you do have to push them at least a little.
So what does that mean?
What helped me the most was when I decided to err on the conservative side, in a big way. I started slow, very slow, then chose to build from there. That's not always an easy path to follow, especially for a Type A personality, when you feel you should be doing more.
But the unfortunate reality is that, yes, there can be entire months where you can't tell if you're getting better, backsliding, or simply moving in place. It's frustrating. But you can take some solace in knowing that many others go through the same thing. You're not alone!