I didn't say otherwise. My point was head is head. A valve adds head the same as pluming does. People seem to think adding a valve partially closed is a terrible thing, but routinely use pluming that is 1/2 the size it should be and think nothing of it.Adding head to the pump.... Correct, that is the ENTIRE point of adding a valve. Add "head" to the pump... but that does not imply anything except that you are reducing the efficiency of the pump.