User blog comment:NeonSpotlight/NeonSpotlight's Balance Changes/@comment-4881935-20130610021020/@comment-3308937-20130611105540

Hmm, not sure why I didn't think of that before. The bonus AD attempts to give Ali a way to be a threat in a teamfight after his initial combo in addition to being a tower killing skill.

With that in mind it'd probably have to be reworked into some sort of persistent damage source like Rammus's tremors or amplify his passive drastically while the ultimate is up or something other than just a huge stat buff to make him feel better and not so outdated.