But then you're back to the initial problem they're trying to solve, which is that some person will get a manager who's way too friendly and promotes too many people, while some other poor soul gets stuck with a harsher manager than never promotes anyone. In short, it's hard to enforce consistency across a company that large.
There's always the route of complaining to your boss' boss. But I guess then Google would actually have to start to give a s#!t about their managers actually performing proper managing tasks. I can imagine though that VPs and their C-level would consider such mundane affairs to be far below Google's aspirations...
But then you're back to the initial problem they're trying to solve, which is that some person will get a manager who's way too friendly and promotes too many people, while some other poor soul gets stuck with a harsher manager than never promotes anyone. In short, it's hard to enforce consistency across a company that large.