Yeah, you read that right. To re-iterate: if you want to code a site and expect it to load even semi-reasonably in Internet Explorer 6 or 7, you probably don’t want to write it or even touch it in Microsoft’s Expression Web Designer. At any rate, not this version of Expression.
Expression Web Designer is very Web 2.0 compatible. It’s the only really big HTML interface that validates directly against the W3C standards, by default checking page-display compatiblity against CSS 2.1, instead of against FF, IE6, or something. It does a very good job at that too, but unfortunately, it’s far ahead of Microsoft’s time.