There can be no "legal force" in any copyright case, because they are inherently fact based. What one person does in one show is irrelevant to what someone else does in another. You've got the concepts mangled: the legal standard is clear and the precedent goes back to common law.
In the law, hypotheticals are often employed, so let me suggest this: give us a hypothetical of a case that clearly ought to result in a judgment in favor of the director under the applicable principles. Then we can bat that around and I feel you'll understand what the law is a lot better.