User-centered design means working with your users all throughout the project.

In my opinion, no single design is apt to be optimal for everyone.

Also note that invariably when we design something that can be used by those with disabilities, we often make it better for everyone.

Successful localization of hydroelectric equipment in the Three Gorges Project means China has been able to design, manufacture, install and operate on its own 700,000 kilowatt water turbine generator sets,

Sure, one can always get the students to relax and be happy - entertained, but although being laid back and relax can also lead to creativity, mostly it means that nothing much gets done.

I'm single-minded. When I'm working on a project, all my attention is there.