So how hard did the AP nerf to Kog hurt the Kaster-Kog mid?

Rito's reasoning behind nerfing his E was that "we didn't want AP kog to waveclear". That's funny because all mages are able to waveclear from rather safe distance. Kog'Maw was already a bit difficult to pull off because he has NO CC and can get dove and ganked easilyy. I understand if they wanted to nerf the early base damage but they nerfed the scaling as well.

Maybe I'm over exaggerating though, I don't play Kog'maw often so I wouldn't know.