I think it *does* log its progress. In fact, it's awefully verbose, I guess :-)
The hardest part is probably to cut-and-slice the image to flash accordingly.
I really like the read-before-write idea. Besides being faster, reading should also consume much less energy. I still didn't get to implement it, though, and that is likely to stay that way until the free days over christmas. And in fact, I already planned to dedicate that time to kindlepdfviewer on my KPW....