Dan, you're right, I missed that.
Still seemed like an overgeneralization.
Completely agree with this and ironbut's statements (and others) -- and disagree with the prejudice against a 2.1 system -- they're quite a common way of monitoring, and many custom installations for mastering basically separate all the elements. And I don't think bookshelf speakers are going to fare any better. I don't care how close you listen to 6 inch woofers in any enclosure, you're just not going to get that low frequency reproduction. You should do the same thing with bookshelf speakers as you did with studio monitors, you'll hear for yourself.
That said, the Dynaudio BM5A's have 7 inch woofers and are said to go down to ~45 Hz or so, so that (7 inch woofers) might be a decent compromise, for non-organ or techno music. (The low E on an electric bass guitar is approximately 41 Hz.) And the 8 inch woofer in the Dynaudio Special 25 is certainly adequate without a sub for most pleasurable listening (although it has a slight midrange suckout that someone who's picky about acoustic piano reproduction might continue to have issue with), but now we're getting back into the category of "pretty big for a desktop" category, so I imagine any speaker with an 8 inch woofer in a decent enclosure is going to have size problems.