Remember 15 second 
cd on PBE
Had stacking magic damage auto's imagine that top lane
Riot is just testing this to see if vayne had a reset or something on kills.
Also if they do go through i think they would nerf base damage cross the board
its riot, they are just going to let her through as is tbh
Riot specifically commented on the Vayne changes, saying the Q change is not happening. While that doesn't 100% mean the other changes are something they plan on doing, it does heavily imply it.
Yeah, and they let the buff of Sivir's Q go through, despite many people warning Riot not to go through with it. It went live, she was heavily broken and then hotfixed, pretty much proving Riot didn't care what's going on PBE unless it's about skins.
