I'm a current employee and subject to the confidentiality agreement, so I can't go into detail here. But you probably know as a former employee that Google often makes incremental improvements to their processes, and the promotion process (including L6+) is no exception. Sorry for the boring corporate-speak. If you really want to know the details, come back! :)
(I realized after re-reading my comment that it was ambiguous; I didn't mean to suggest that your eventual yes would have turned into a no. I merely meant that the process to get there today would have been different, and hopefully more predictably efficient.)
EDIT: actually there is one hugely confidential scoop that certainly would have affected you and that I'm totally going to share with you. They no longer have promotion jackets. (Readers, these were lightweight zippered jackets or pullovers that read "Google Engineering" near the breast-pocket area. They were so understated that they triggered this sort of CrossFit reflex that compelled some wearers to tell everyone within earshot about them.) In the past couple years the company has tried to tone down promotion celebrations, at least in Tech, so many of the broadcasted congratulations are gone, along with the jackets. Fine with me -- promotion season is nice for those who get what they asked for, painful for those who didn't, and in either case something that should be private by default, like your salary.
