No. I meant integrating would create cores on the vassal land. For example:
Vassal has 10 provinces with exactly 10 development each. It cost me 800 diplo points to integrate.
I'm sending a diplomat and when he has 80/800 progress one province of the vassal's domain has my tag's core on it.
So now I can recall diplomat and still keep progress because now I have one core so it costs me 720 diplo to integrate the vassal.
If my diplomat got to 400/800 he would create 5 cores.
I hope you understand my point.