I have a position relative container with my rounded corners positioned absolutely in the corners. If you look at the example/link you'll see that if you move your window left to right a line appears and disappears on the right side of the bottom box in IE6 only. Note: the top box would have the same problem, but it happens to be at a width that it doesn't. I could however find a width in which it does. So... it's not a haslayout problem - what is it? Thanks!
Why would you need to throw it into quirks mode though - for IE7?
You don't have to.. it just means others will see what you're saying without having to open IE6, maybe some don't have multi environments, it's simply a tip to quick check some IE6 things in your IE7
I think that some of the IE6 questions might be going unanswered because folks don't recognise the "bug" and don't have multi IE's installed to test, but anyway, sorry if it added confusion.
Note: it, the quirks switch, does not show everything the same, it is still quirks mode after all but for some testing between IE6 & 7 it's a handy switch (like hover functionality and some other bugs!)