The thing that got me was: The (x)psi of boost is acting on the injector, slowing down the flow of fuel. So if you have 45psi of fuel in the rail and you boost 10psi; that 10psi is going to act on the injector, lowering the fuel pressure to 35psi. It's physics like said above. So you need that 1:1 regulator to balance the fuel psi to boost psi, keeping the FP constant. I know where you're comming from, SFMU School of Thought.

ALvin