On the other hand, the more manufactured background you have, the more likely something is to trip you up, either because you misremembered it when talking to

On the other hand, the more manufactured background you have, the more likely something is to trip you up, either because you misremembered it when talking to somebody or you ran into somebody who was involved in the real world situation and knows you were not. The best way to get away with a fake past is to be vague, but not so vague as to arouse people's curiosity or suspicions.