Canon is not entirely clear why, but in general it is a Very Bad Idea for non-s'Ffalenn to try to deal with this particular magic sword.

"The runs are for endurance. You also need to build other muscle."

He holds out an arm, and flexes. Despite the fact that he still looks like he's got the body of a teenager, despite the fact that he's skinny and slight and could almost pass as a child, and despite the silk of his shirt his arm is corded with muscle,

"You are old, to begin, but Tom is older and does quite well."