They were talking about taking a value off of one list and adding it to a different one, which doesn't require an allocation, but the entity is never on more than one list at a time in that scenario.

That said, you can add an entity onto multiple lists if it contains multiple nodes embedded inside. You have to keep track of which nodes are attached to which lists though (Which generally just means being consistent on which you use where). If you give them decent names, then it's not usually a problem, but it can sometimes get a little confusing if you're not careful.

Obviously not