Every co. is different it seems.The one that makes most sense is putting the breaker on one shot and never rely on a fuse to open merely because of the fuse thats there.Did someone slug it.Maybe they used a T fuse instead of a K fuse.Ya know the crew that came from out of town to work that storm that blew threw and all they had was T fuses.Just something to bare in mind.Ya just never know.Trust me I seen this as an apprentice and thankfully the breaker finally opened before the wire burned down.