On the contrary, it is useful to have a comprehensive, substantive measure of technical skills. Having one does not preclude additional assessments, as you assume. I have been continually disappointed with the lack of extensiveness in technical interviews, as a candidate, but also as an interviewer when reviewing other interviewer assessments of potential candidates. I have yet to meet a programmer who doesn't believe they are very good at what they do and I believe this problem is due in large part to the shoot-from-the-hip approach that the industry takes at the interview stage.
The problem is that you're relying on interviews to hire someone who will hopefully work with you for years to come. Would you interview and pick your wife or husband in one day? Would a table like the above help?
