[28inch]

"As far as RWD taking twice as long to design and implement, perhaps this is just a question of experience. "

That is actualy a rather bold statement and might be true for common patterns. Scaling, (and pricing) RWD is really challenging for me when it comes to unkonwn things like this:

http://www.itv.com/

Fresh identity, responsive front page. All nice and smooth,right?

But how about this? http://www.itv.com/tvguide/

well... I guess they just gave it up here. I`m not saying it is impossible to implement but I have no freakin idea how to estimate a deadline for something like this. And itv is a big company, with a decent budget.

An other example is the famous bostonglobe.com. Beautiful site, working nicely too, but it has freakin ~12K lines in the css!

So plenty of blind spots all over the place, especially for small teams and individuals like me, when it comes to estimating, scaling and pricing.