Hypothetical Contactor Question?

Hi; Some may prefer to call this question highly pathetic; In the attached diagram, which came from a Chevelle, or Holden as we call them in Australia, as each contactor steps up the voltage I read it as shutting off the previous lesser voltage contact. Correct? So what would happen if each contactor stayed closed as the voltage was increased? To my untrained thinking the full voltage would still be reached but with less load on the higher end cabling with each step cable still distributing it's own voltage with less heat at the higher end. I await correction.(that's right; I still can't afford a controller)