Since I trust the market for financial matters more than bloggers, I went to Google finance and compared the performance of Canon stock (TYO:7751) with Nikon stock (TYO:7731): year to date Canon lost 27.57% while Nikon gained 22.80%. I guess that's enough to judge the respective managements and products. All the rest is bla bla bla...
Both Canon and Nikon are recovering from the devastating effects of tsunamis in Japan and Indonesia. It has been a volatile couple of years for both companies and is likely to remain so as the effects of lost production facilites and investment in new ones continues to be felt. This is the greater context, DXO mark and some bloggers will probably have some effect, but largely against the greater adversities I think it is bla bla bla
This is the "beauty" of forums and blogs: one doesn't have to be smart or even just to understand what others wrote; it's enough if one writes something, anything, and all will be fine.
Now I elaborate: I know all that you wrote, but did you realize that the performance of Nikon is +22.80% and not -22.80%?
It's not "recovering", it's doing quite well indeed in this adverse market. The opposite is true for Canon.
If you moreover want to see the effect of any event on the stock price further in the past, just again look at both charts (TYO:7751 and TYO:7731) on Google finance: you'd be amazed to see how analysts quantify in terms of price change all the bla bla bla; most of it amounts to zero.