PM Wants Justification for Including Search & Help on Web Site Revision

Hello all,
It’s always been a “given” to me that a “good” commercial Web site includes context-sensitive help and a search capability.

However, on my current project as a Business Analyst, the Project Manager wants “justification” for including Help and Search as requirements. (And won’t take the Solution Architect’s word either).

Anyone want to give me some “justification” or point to some appropriate guru who knows that Help and Search are critical?

Thanks.