I didn't understand about minor elements. I told about metal measure in pure oxides, which are very close to stoichiometric compound (Fe2O3, Cu2O etc.)
Yes, I performed careful wavescans to check the peak shifts and background positions.
Totals are 98.5-99.5. I used both: measured or specify (not measured) oxygen concentration.
My issue is absolutely the same question of your topic! Thank you!
But my results didn't change if I use "calculate excess oxygen from Ferrous/Ferric ratio" checkbox (attached file). In excel file I see zeroes in FeO, Fe2O3, excess oxygen etc. columns.