Sometimes up-dosing will be required with certain beans/roasts that you need grind a bit finer (thereby compressing more in the PF). I've found that by factoring in a simple settling tap on the bench before my NSEW sweeping gives me a good baseline - then if I want a bit extra in the PF, I just add another light tap. If I want less - tap lightly! That way, there is no double tamp required.
I don't weigh either - this technique works pretty well over here :-)