I won't agree to anything that is as vague as "some mechanism".
*sigh*
I was trying to see if you would agree in principle to the feature, with the mechanism to be determined later, rather than asking if you would agree to this method or that one.
Well, fine:
another alternative would be...
1) ruler click special link to attempt create duchy from empty region (different from your average duchy link from townsland/city/stronghold)
2) the duke gets an event message asking yes/no.
3) if yes. created. if no. too bad.
This seems pretty reasonable. Would you be willing to support this? Either as creating the Duchy with the Ruler as both Lord and Duke, or as creating it with just that region in it, and no Duke yet (the Ruler could then appoint a Duke, who could appoint himself Lord, or not)?