Water pressure regulator question (yet another)

NEVER use more than 1 pressure regulator at a time. Adding an extra will indeed diminish flow and pressure. I have a hook up at work to demonstrate this. I connect a standard in line RV regulator to the end of the shop hose(shop about 65 psi). I then add the 2nd and then 3rd Regulator and the customer sees that the volume pressure is almost none. MY preference is to have the Water Regulator(adjustable) at the CG faucet to help protect my potable feed hose from the sun and excess pressure. Doug