No, the quiet casting is only for spells, not enchanted items. Why would a spell perk affect a sword?
Well, there are some weird things that happen in this game. So it is possible. Why would a potion affect a staff, why won't a follower use a really good bow, why is dual wielding swords faster than dual wielding daggers? Anything is possible in this game. I'm just trying to understand it the best I can.