Done this whole process as well. Every year, in fact. I've interviewed with quite a few top Bay area companies with quite a few going to onsite.
I never got an offer though and the only thing I can say that differentiates me from this person in terms of how we studied is the part where you practice with other peers. I've done this maybe once or twice a few years ago. I think in order to get to these companies you need to practice with peers. Preferably with ones who have made it through. Unfortunately, in my experience, it can be hard to find peers willing to do such things. I'll continue to make half (or less) of what I could be making if I was at some top public company. And this area will continue to be out of my reach financially because of that.
I never got an offer though and the only thing I can say that differentiates me from this person in terms of how we studied is the part where you practice with other peers. I've done this maybe once or twice a few years ago. I think in order to get to these companies you need to practice with peers. Preferably with ones who have made it through. Unfortunately, in my experience, it can be hard to find peers willing to do such things. I'll continue to make half (or less) of what I could be making if I was at some top public company. And this area will continue to be out of my reach financially because of that.