Interesting, but correct me if I'm wrong... but does this technique only improve the performance on multiple choice questions where the correct answer is one of

Interesting, but correct me if I'm wrong... but does this technique only improve the performance on multiple choice questions where the correct answer is one of those choices? Unfortunately I don't see that as being very useful since I think a lot of use cases involve questions to the AI where you don't know the answer in advance or else why would you ask it except to test the AI's capabilities.