Your pot hole analogy is fairly accurate. You could think of cars constantly driving on the filled pot holes as impacts on your ankle. Eventually the filled pot hole will crack again. From my experience I would very much categorize MF as only a temporary solution, but with the caveat being it depends on what sort of activity you do after full recovery and PT.
I've spent some of my time scouring the internet to see what NBA athletes have experienced with MF. Some athletes recovered really well and performed with no issues, while others failed shortly after. So I'd make a guess that it goes back to what you and many others have echoed on this forum: it depends on where and how big the lesion(s) are. But I'd add one more piece to it: it likely also depends on how the fibro cartilage grows back as well. Surgeons don't shape the cartilage, they only trigger the growth of it. Suppose that the fibro cartilage grows back in such a way that it isn't stable enough to take impact. On the other hand, it's possible that it grows back in just the right shape that it can take some level of impact with no negative consequence. I'd say there's just so much that goes into it that it can fail on multiple points.
FWIW, I can give you an idea of my activities after the surgery. My surgery was performed on November 11, 2010. By March 15th 2011, I was on plane to Taipei. Taipei is very much a walking city, and I was completely fine. Prior to my flight I was diligent with following the doctor's recovery instructions and then subsequently followed a very strict PT schedule. In a nutshell, by 5 months I was completely cleared for my trip and I felt like a new man. If you wait, it's fine too. But I thought I'd let you know how my experience was in case you changed your mind.
Although I really hope you find a surgeon that knows more about new treatment, such as Denovo. To be frank, all treatments are likely going to be some kind of "filling the pot hole" solution. I don't see how else it can be fixed. The next logical thought would be, which material is BEST for filling that hole?