> She yells at her computer, doesn't know what a twitter is, and struggles to find windows she's minimized.

> You should design with your mother in mind. If she can't understand your site, others will struggle as well.

I'm not sure your mother represents the average user, and likely does not fit the target demographic of most web sites/applications.

Maybe I'm missing something...but how is this useful? I get that we should all design for actual people. But most of the time, "most people" (and perhaps more importantly, most paying customers) aren't going to be your mom (or people like her).