The node gives +200% increased frequency, 1s/3 = 0.33 seconds.
Instead of once per 0.33 seconds it’s firing about once per .72 seconds.
I remember this shooting faster the last time I used it so it was rather strange when I felt like it wasn’t really changing much with each point. It’s only casting hungering souls 11 times in 8 seconds when it should be casting 24.