Agrimmon Are you basing this on the match of what Simon says ingame to the text in Fulminato's Calculator?
The latter is a little unclear in the Calculator. Simon has the same opening lines if you complete the section with an investigation score of 15+ as that with a score of 14-5. "We Understand Enough of the Political Situation to Have a Small Impact...". But Fulminato abbreviated the 15+ line to "We Understand Enough of the Political [...] Do Something More Benevolent" in order to include the first line that doesn't appear in the 14-5 version, which is "But we can also have him occasionally do something more benevolent."
If you want a pair of single line that tells you whether you've hit the 15 threshold in game, look for Uyae to say "Kindness along with pragmatism! Most wonderful!". If you got more than 20, Simon will say "I have an idea. It's not perfect, but I think it's the best we can do given that we don't have deep experience in Zirantian politics..."