The thing that concerns me with many responsive websites out there is that its possible to view a mobile or tablet optimised layout on a desktop since the website is programmed to respond to the width of the users window, not device width. I cant understand why anyone would want this, yet many big organisations are going with this approach. I.e check out
Currys | Sale Now On. Electricals, Kitchen Appliances & Latest Technology - look how you can totally compromise the desktop experience just because you happen to have your browser set a bit narrower so you trigger a clearly ipad or mobile optimised layout. I really dont understand why you would want this?
I think part of it is confusion down to what is and is not possible. In my opinion putting a mobile layout on a desktop, or a tablet layout on desktop risks watering down the impact of the design and overall experience. These devices provide a different experience! Its not just about screen width since buttons and navigation on smaller devices are often totally different - so why make this possible to view these on a desktop? A tablet experience is optimised for that device - hand held and operated by touch. In my opinion it should not be possible to view a tablet layout on a desktop and indeed a mobile layout on a desktop but it seems to be the norm with responsive design. Simple techniques to detect the device-width rather than the window width will make it possible to deliver the best possible experience by not mixing up layouts and providing the layout specific to the device the user is using.
I believe the BBC have got it right, or at least partly right. They have a desktop website which makes use of the larger screen size. If people are viewing it on a small window and cannot read the whole page they probably know by now how to maximise the window. I think in 2012 this is a fair assumption? The BBC site also responds to individual groups of devices, so smart phones with varying screen sizes (and portrait / landscape mode) and tablets with there own range of screen sizes - so the experience is always optimised to the relevant device. I think the single URL approach can be used here in a similar way by using the other responsive principles, but focusing more on device-width rather than the window of the window. I just think 'responsive design' or 'adaptive design?' could be more intelligent and respond within the parameters of device groups. There you go, intelligent responsive design - the future ;)