It doesn't matter if you can stack it, take Renekton for instance, you go in and stun them, now they have three stacks, but you have already used your biggest attack. You can auto and follow up with a Q and now you've got the stacks but guess what, your damage is done. Go ahead and stick them to utilize the arpen, but now your REALLY committed to the engagement and you've JUST started to do the damage.
This doesn't help casters at all once team fighting comes since who has AOEs that can actually hit several targets with physical damage, then come off CD before the stacks expire? You aren't helping the ADC at all with this item.
AD Casters should be winning 1v1s mid game anyway, and that is when this item would really be good, since you have some room to chase and should have a phage or something... but later game you are still irrelevant since this item will never be stacking without you getting gibbed.
Stop being bad at this game because you obviously are --- Burn the heretic. Kill the mutant. Purge the unclean. Lol IGN- ThatKillerBenoit
This item is godly for bruisers that already build brutalizer. Its useless on most other champions. If you are getting it as ADC, you are doing it wrong. --- http://img189.imageshack.us/img189/1678/87591610.jpg
It serves a new purpose, so it's indeterminate until we can use it. --- Carpe Diem, Memento Mori Take my hand and on dark wings we shall fly away from this corrupt place. Together we will experience the world as it was meant to be