User blog comment:StrategicMagic/Vayne - Carry? Yes. AD? No./@comment-4680018-20120821175752

Your build works as Tank buster, I'd imagine this build doing well against a team of mostly bruiser type champions. But against more squishy champions that will be able to do more burst damage, you will die before your true damage has a chance to kill them. Considering that squishies have less hp it will mitigate the damage your silver bolts and madreds will do. In addition squishy champs usually build some kind of life steal or spell vamp, that combined with their huge burst will allow them to heal the damage you deal further mitigating AS Vayne's effectiveness on the battlefield.

To add, a teamfight will generally only last about ten seconds. Assuming you have maxed AS the whole time you'd get off 25 attacks which equals 25 auto attacks and 8 silver bolt procs, if you are shooting the entire time. Now here is my issue with relying on silver bolt for damage. In a team fight you might not get the chance to land those procs or that many of them. Plus you have to focus on one target to get the procs to work. During the time you are focusing a target you will likely be CC'd or knocked away or maybe just misclick another target, either way you would have to rebuild those stacks to get the damage. I know that it would only take you about a second and a half to get the proc but that is a long time in a teamfight and it makes you a target to any smart tank or assassin on their team. KeatonK brings up the good point that you also would need a matching support to help you out. Someone that can "babysit" you all early game. A cc support like Leona, Alistar, Naut, Janna, etc. If you have a duo buddy who will support you then this problem can be solved with improved teamwork on yourside. AS Vayne is team reliant and though the game itself is team oriented, to me AS Vayne is too heavily team reliant. You would need extra support from your team that AD Vayne would generally not need.

Your runes also bug me. If you sacrifice armor for gold regen you'd end up with about 1200 more gold in a 40 minute game. However since, as you stated, Vayne's weakness is her early game. That gold will come up late game, but in the early phases you are much more vulnerable to ganks and harrass in general. These two factors make it much more likely that you will be pushed out of lane which will cause you to lose experience. Your gold regen may keep on on par with the enemy's gold count but it won't make up for the lost experience. If you are forced out of lane enough you will fall behind in level giving your opponent a larger advantage.

I can appreciate the time you are putting into AS Vayne but she has several flaws that make her difficult to use. Her lack of burst damage combined with her heavy reliance on her teammates make her a hinderance on your team. Yes this can work maybe in normal where people don't really take the game too seriously but in a high ELO battlefield your AS Vayne will not meet up to par vs a normal AD carry.