I searched GIS.SE for "Desktop vs. Mobile" and didn't get anything helpful, so I guess I'll be the one to ask.
Question: With respect to Internet mapping applications, is it better to have separate sites for desktop and mobile, or to pursue one highly adaptable site (Responsive Web Design) that attempts a best-fit across all devices?
Background: A quick review of this problem reveals this article (Nielsen, April 10 2012) where the author advocates separate sites for desktop and mobile, as well as this rather strong rebuttal (Lawson, April 19 2012) encouraging development of one well-planned site capable of serving a variety of devices. Other articles discuss various pros and cons, but ultimately remain neutral.   
My Own Experience: My first attempt at this was the one-site-fits-all approach, and while it renders properly on most mobile devices, I find it lacking with respect to the total experience. I want better use of screen area. I want bigger control surfaces to prevent "fat fingering" consequences. And frankly, unlike Lawson, I think our mobile users probably do have different goals than our desktop users. I doubt our mobile users care about our 2-foot elevation contours, but I bet they commonly want as much parcel data as they can get, preferably in a layout that's convenient on mobile.
At the same time, maintaining two separate web mapping clients seems like a bad idea. ..then again, maybe that's a false economy? Perhaps two simpler, more focused sites would be easier to maintain than one burgeoning, more complex site?
Denouement: The Lawson article suggests there will always be edge cases favoring multiple sites over responsive design, and I'm starting to believe Internet mapping is one of the edge cases. So I'm asking the community to provide insight. Which of these strategies do you prefer and why? I figure the better strategy should organically up-vote its way to the top, providing a kind of de facto authentication of the approach that's better suited for Internet mapping applications.