I have met a few shardbearers with little to no combat experience. One was a doctor. While he largely relied on us for protection, he still made attempts to learn, and arm himself. All one need do is take the initiative, or learn on the field if they are that unlucky.

[Essentially, he had no sympathy for people that cowered and hid, or complained about not being able to fight. Caer Scima was not a kind place, and there was ample opportunity to learn.]