Muscle Armor effectiveness

[Dan Howard]

Don't Roman Emperors use Linen armor? Was this description Linothorax or Linen Musculata?

As [Galba] was offering sacrifice on the morning before he was killed, a soothsayer warned him again and again to look out for danger, since assassins were not far off. Not long after this he learned that Otho held possession of the Camp, and when several advised him to proceed thither as soon as possible — for they said that he could win the day by his presence and prestige — he decided to do no more than hold his present position and strengthen it by getting together a guard of the legionaries, who were encamped in many different quarters of the city. He did however put on a linen cuirass, though he openly declared that it would afford little protection against so many swords

That seems a pretty broad generalization to draw from a single passage. At best it tells us that one emperor wore linen armour on one occasion.