One need not manifest fear in repetitive ways; that said, Quertus moving to take cover behind <largest party member> / Armus moving to provide cover for <PC with better defenses> being repetitive made for both observable character traits, and an advantage that made bad impostors easy to spot.
If it hasn't been mentioned yet, the severity of the cowardice can play a big part on how it is received by the table. As can the specific implementation thereof.