6 months have elapsed since the surgery. The defective surfaces have already healed.
So don't lose sleep over cartilage not "setting."
The bigger concern is there being no cartilage re-growth. And of course over-compensation for his left knee and persistent stiffness. Much of that stiffness won't necessarily go away depending on how the cartilage sealed over the joint - there is a distance between the formation and lodging site. The size of the degenerative area pre-operativly for Amare is a much more significant predictor of his recovery than 25 minutes of NBA action in March.
You sound like you know a good deal about microfracture. You are correct, the re-growth of the cartilage is the most important indicator, and I think we have to assume AS's has grown back to a reasonable degree, they were doing MRI's on him all the time. Knee strength, the size of the defect, and how much grew back are the important factors in the return of a microfracture recipient.
However...
I am a veteran of the microfracture technique. While data has shown that 6 months is enough time for cartilage to grow and solidify enough for a return to athletics, my own experience, the numerous orthopaedists and therapists I have dealt with, and my observations of athletes who have undergone microfracture have demonstrated to my satisfaction that returning to heavy duty sports activity after 6 months ain't enough time, just from the aspect of the stress put on the new cartilage.
My cartilage did grow back decently, I rehabed to a new level of strength, I returned to sports after more than 6 months and it was shredded again in a short period of time.
In fact, more than one of the orthaepedists I have gone to who are affiliated with professional sports franchises have compared going back to rigorous athletic activity 6 months after microfracture to "trampling fresh seedlings". In essence, newly generated cartlage can collapse under too much stress.
This is especially true for those who have the technique done on weight-bearing areas of their knee, unlike Jason Kidd. AS you know, the cartilage that grows back is not the same as the stuff that is lost, it is not as good, it is more like "scab-cartilage". And 6 months isn't enough time for it to toughen for the big time.
I am not saying that it can't be done, but why take the risk?
oohah