[quote=@Wraithblade6]Some moves can be auto hits if they are highly probable. Like, if your weapon is suddenly scalding hot, you're probably going to drop it. Also, there is already a plan in action for her to use the other blade. It was preemptively intended. 
[/quote]

Well, swords aren't bare metal and...

Youmu dual-wields? She doesn't need to drop one sword to use the other.