I'm not sure how that's relevant, misunderstandings of your post's parent aside.
On the subject of unsupported browser tests, a question: how much value do you actually derive in real-world browsing from SMIL, the remaining area of Acid3 not supported in Firefox? (Aside from being able to run Acid3 and see it pass, that is.) How much do you expect you would derive if SMIL support were widespread in browsers? I think the answer is very little, and I think my opinion deserves at least some consideration given that Ian has repeatedly stated that adding the SVG-related tests to Acid3 was a mistake. (I don't know that my questions touch upon the reasons Ian has for thinking that a mistake, but I do suspect unusefulness in general, even in an ideal world of SMIL-supporting browsers, played a factor.)
Acid2 was good in my book, but Acid3 was much more of a grab bag. It mostly consisted of browser bugs found by searching through bug databases and through suggestions to Ian (I suggested a few, actually, based on knowledge of various Mozilla bugs), not something that deliberately set out to test functionality useful to web developers in general. Some of the fixes were utterly trivial (I fixed one that was a one-line change); others were more involved but not particularly difficult (I fixed several of these as well). Really, tho, the fundamental problem was that Acid2 tested things developers wanted to use but couldn't; Acid3 tested many things which will never see much use by developers.