My point is. The metering rod sits inside the hole in the jet, it has different ODs and as it moves up and down it changes how much fuel can flow thru the jet. If (and I don't know the answer from the literature you are reading) that was taken into account, just up the jet size. But it seems to me that the jet size being opened up 20 % might make the metering rods moot. They will still have the effect of making the hole in the jet smaller or larger but the percentage will be different.
Think of it this way...
If you have a 12" diameter hole and you put an 8" diameter plug in it you will reduce the amount of flow of what ever you are trying to push thru the 12" dia hole. Now open the 12" hole to 24" that same 8" dia plug is not going to restrict the same percentage of flow.
Hope that makes sense.
I wish a carb tuner would chime in.
Maybe start a new thread titled "carb tuning for achohol"
