Changing a DefaultValue under A_Additive_ProductionPerMaterials not working

In CorePlayerAbilities.xml, I changed the DefaultValue under A_Additive_ProductionPerMaterials from 8, to various values from 80 to 8000, and found no effect when starting new games.  Production per Materials remained at 8, regardless of what number I put in the file. Changing the value in A_Additive_GoldTakeAwayPerTaxPercentage likewise had no effect.  Can anyone tell me what I'm missing?