Whelp, since the game's explanations for hovering platforms, block puzzles that reset themselves when you leave the room, the leveling of your weapons against certain monsters when you whack them enough, why enemies vanish when you kill them, and when you learn new moves is arcane magick through the power of the Dark, the reason the weapons don't break can be that too.
Where are these lemmings going? The
Super Nintendo Super Shire! Hop in line and follow them there!