Factors two and three relate to character. Factors four-six deal with credibility. Factor seven is the most important in that it gives the judge leeway. Since the full board does not hear the witness, the judge can always base his or her decision on the demeanor of the witness with little fear of reversal. Never Attack Character or Credibility when you can attack Competence.
Judges hate to make credibility determinations.
No one likes to call another person a liar. Yet that's what a judge must do when he or she finds that a witness is not credible. If a judge sustains a character attack he or she is calling the witness a habitual liar. On the other hand, there is no stigma in saying that their witness could not remember or see as well as your witness. It is assumed that all witnesses are testifying to the best of their recollections.