A question came up during Bellum as to whether or not monks needed a headband to deflect missile weapons. As the elder within earshot, I said "no", but there was of course discussion. Looks like this is one of the rare times when I was right:
The Jan 3013 rulebook wrote:Monks
Monk characters strive for rigorous physical and mental discipline. Due to their intense reliance on order, they must be of lawful alignment whether good, neutral, or evil, and they must always remain true to their alignment. Monks may use any weapons except shieldbreaking weapons, bows, and crossbows. Monks may not wear any armor or use any type of shield.
All Monks have the skill of 'Missile Deflection' at 1st rank. This skill allows them to use their hands, feet, or weapon to purposefully deflect any incoming non-magical missile weapon. The Monk may deflect the Arrow of Piercing, but not the Javelin of Lightning (see Relics in Chapter seven). The Monk may not deflect any spell or spell like effect. If the Monk is struck unaware, misses the missile, or attempts to use this skill with any body part other than his hands or feet, normal damage is taken. Monks using this skill should call out "Monk," upon making a deflection.
At 3rd rank, Monks obtain Leather Skin. This ability gives them the equivalent of leather armor (AC1) from head to toe at all times. A Monk with this ability must wear an orange headband with a blue circle in the center. At 4th rank, a Monk gains the ability to ‘Cure Light Wounds’ on himself only. To perform this skill, the Monk must meditate for 60 seconds without interruption. During meditation, the Monk is not permitted to move or speak. Once completed, the Monk has fully healed one light wound anywhere on his body. This skill also restores any damage taken to the Monk’s leather armor skin from the Leather Skin skill.
Notice that there is no mention of the headband as either a required class symbol in the general paragraph, or as required for the Missile Deflection skill in the second. It's not mentioned until the Leather Skin ability. You don't need to wear your headband armor to be a Druid, Mage or Warrior Mage, either.
Of course, the Magistrate is free to weigh in, but it looks pretty clear to me.