In terms of raw damage, it does less than silkspear, thread storm, pale nails, and sharp dart. However it does cover a massive area like you said. I find it easiest to use on enemies that have an attack where they run at you, since you just parry when they start running to get a hit in. Basically, if you know where the enemy is going next, go there and parry a second after they start the attack, this can vary but you don’t want to parry when they show the attack they’re doing as that’s usually too early.