Re watchful waiting, I can certainly understand your point as it is certainly likely any PCa is growing if even at a slow rate.
In my case, with an intermediate grade cancer, I didn't qualify for WW and would not have done it. However, I can understand the logic of men who do. If my cancer had graded out at a 5 or 6 with 1 core out of 16 at 5%, I think I probably would have waited for treatment (WW). In the ongoing Johns Hopkins WW program, 2/3 of the men in the program have not shown disease progression that would indicate that treatment is needed (of course that means that 1/3 eventually did need treatment).
As I have said before, I think that there is also a pyschological aspect of treatment choice that has to do with the willingness to take risk. Any WW patient would have to have the ability and willingness to put some of the worry aside because, clearly, the cancer is still there and may be growing to "treatment size". Or, it may grow to an advanced stage.
And, if I was 75 instead of 62 years old...I think it would be an easier choice to WW with an early stage cancer since the odds would be high that something else would kill me first.
Anyway, this remains an interesting topic of debate...