How do I make dynamo "forget" what it did in a previous section?

Dear Lazy BIM,

I got the same issue recently but I have also happily found that with the new version of Revit 2018.1 and the new Dynamo Player you can run multiple times the same tool on different elements. It does not update the ID selection but it will keep the previous “bake”.
Worths to give a try if you can