[There's a moment where it seems he's realizing the mistake he made, assuming Fuyuhiko was referring to weapons rather than the weakness itself, but then he continues unfazed.]

Something like that would only be practical if there were daylight to appear in. If it were late at night, a weapon of sunlight would be invaluable. If you were to come against an enemy with no other weaknesses in any form of twilight battle, they would have clear advantage without it.

[Still missing the point probably but......]