Forgive me for jumping in here again. Up to a point, I agree with the
sentiment expressed above. Obviously if one is going to enjoy SF and
sci-fi (and most readers of this message presumably know the
difference) you have to be willing to bend the rules a bit. When I
read SF, for example, I am willing to consider the possibility of faster
than light travel, even though our present understanding of physics is
against it. But if too many rules are bent, eventually I reach a point
where I am no longer willing to do this.