The interviewer: I mean, come on, Nathan. Realistically, now. How many client projects are going to be able to afford their own dedicated Experience Designer? How many would be better served by a qualified IA who's maybe attended something like the AIGA conference - but used that as a conceptual overlay, informing a sound underlying architecture?Sorry, but it's all about the money. UI designers, UX specialists, Info Architects and the people they work with must always make value judgments on the tasks they are assigned, or take on themselves, and squeeze maximum value out of their efforts to complete the task.
Nathan: How many can afford an IA? Of those who can, how many actually have one on board? This isn't an issue of money and budgets. It's one of context and approach. A good IA might also be into looking at the larger experience (beyond the information organization, presentation, and visualization issues). That's awesome. But that's more than the job description for IA.
Value judgments need to be made.
Is a week's worth of UI review and usability studies going to help the web app? Yes? Do I have the time and money to do that? No? I don't care if 'context and approach' are what Nathan thinks is important, the client thinks quality at a low price is importent, so we need to make efforts to satisfy that need. Context, approach and good intentions don't pay the mortgage.