Oh, well... I Wasn't aware he was hiding it, but Lavulman brings up a rather good point. The average length of a real-life rapier is nearly four feet; imagine hiding a four foot sword on your person? His own weapon would be of similar scale in comparison to his person, one would imagine. Even a long cloak would make hiding this exceptionally difficult. I thought the weapon was the reason he had tried to pass himself off as a knight?