I came across this site while we were working on our presentation. Jackie vouched for how awesome the site is (Which it is! Check out the whole site Smashing Magazine ) so I began to peruse the various offerings. The first article that caught my eye was entitled “The Myth of the Sophisticated User“. The article gives a great running explanation of the feelings and challenges of two users, a sophisticated one and a non sophisticated one. It identifies their respective problems and suggests that you must design with both in mind and if you ignore one type of user, your site will not be as successful as it could be.
I will leave you with one line from the article to ponder.
“…no line of instruction will compensate for a bad design.”
Katie Cissell 
Interesting read. I believe that what differentiates a good design from a bad design is the way the design handles a non sophisticated user. One example that comes to my mind is iOS vs Android. My grandma can use an iPhone but not an Android. But a sophisticated user would maybe appreciate the power and flexibility Android provides.