Mythical Valepiercer and RR

http://www.grimtools.com/db/items/8530

Does it works? I don’t see visual indication when attacking with Hellhound.

I assume it does but I never could shave any time off of kills with this or maxed foul eruption. I’ve personally been wondering how effective the flat RR is since last patch but haven’t had time to rigorously test whether they are noticeably working or not.