Using the Papyrus script function AddForm on a FormList DOES persist through a save
Using the Papyrus script function AddForm on a LeveledItem DOES NOT persist through a save (WHY?)

I have not tried adding to the other two Leveled lists but I suspect they won't either.

This will probably disappear in the mass of bugs and other more important tasks to be fixed but I recently discovered that LeveledItem additions via script do not persist with saves, yet FormLists do. This might be common knowledge but it seems rather dumb to have both list types append-able via script, but only one of the two is actually useful. If the LeveledItem changes do not persist through a save, there isn't any point to adding to them in the first place and there is no way around the problem as there is no way in script to tell if a game has been started.

The purpose of dynamically changing lists via script is to avoid plugin conflict (Meaning you don't need to manually edit the list in the Creation Kit and cause one plugin to override the other)