Since the moderator presides over the debate...
"Neither candidate appeared Presidential, nor did the moderator appear presidential".
- presidential: of or relating to a president
- president: one who presides
- http://www.dictionary.com/browse/presidential?s=t
Separate from President with a capital P, "the highest executive officer of a modern republic"
It sounds horrible, but it fits so well.
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Neither candidate appeared Presidential, nor did the moderator appear to moderate.
- With the candidates we are concerned with their appearance and presentation for a future Presidency, with the moderator we are concerned with their behaviour during the debate. did not appear to moderate , using a verb, speaks to their inaction and lack of control over the debate.