"What? The item was not really itemized for AD casters at all and was instead good on bruisers and ADs alike?"
Just about any item that's good on AD casters will be good on AD's in general, hence why AD casters have such bad itemization.
and this is why they've been so reluctant to release a new AD caster item. They knew it would be very difficult to balance. Although honestly, it's a bit niche on AD carries, depends on who uses it.
Very good on bruisers though, its true. But i don't have much idea as to how they'll differentiate between the two. CDR, AD, Arpen, these are all the core stats necessary for a good AD caster item, and they're all good on bruisers too....
"That is why war is so tragic. To win means to make victims of your opponents and give birth to hatred." - Kratos Aurion, Tales of Symphonia