One member of our PFS groups insists that the improved damage evolution for the eidolon follows the same die progression as improved natural attack. The rest of us think that it follows the die progression of the weapon chart.
I have pointed out threads on these forums that specifically refer to these two abilities being different, and even stacking, but he insists that the people on these forums are "interpreting it incorrectly".
Can I get a ruling on this to stop the quarreling in our group?