Are you sure the brief is to design a comfortable chair that people can sit in for extended periods of time?
The new terminal at Heathrow has only ~200 chairs for millions of people to use every year - the key reason being BAA makes most of their money from the duty free shopping, and people wont shop if they have a comfortable place to sit. So I imagine the chairs were selected specifically to be uncomfortable for anything other than a brief break.
Bring the hate! 