FYI, there are a few images that are served from non-PP servers, even if they appear to be a single pixel.
I can't cut/paste the text, so here's a screen cap to show you.
(Also sucks that PNG isn't an allowable upload graphic format)
Sure, it may be that the core PP pages are served from you, but the reality is that more than a few pages have embedded content in them of some sort or another.