If you had a superstrong catwalk a light year in length, shaking it at one end would only cause the other end to shake after a year.
I think you're misunderstanding my post.
What I was demonstrating was a kind of vehicle for this.
Each box would be individually propelled within each consecutive one.
They would end up having ridiculous proportions though, it's just a concept that would theoretically work for faster-than-light passenger travel.