1. Confidence is over-rated as a virtue
2. Confidence without competance is impudence.
3. Knowledge is confidence that you can share.
4. An employer or employee that doesn't know this, cannot help you in the long-run and is not worth your investment.
5. Therefore, whether seeking or sifting for a job-match, value competance far and away: and, though this leads to humility, it will not be to your detrement.

I agree on the first 3 points, particularly for technical positions.   If your boss is consciously aware of the difference between confidence and comptetance, it makes life a lot better.   In my experience, those managers have been the minority.   8^(   Of course, YMMV.
    cheers,
    Don
    striving for Perl Adept
    (it's pronounced "why-bick")