A distinct and highly praised quality of a game world is immersiveness.
As I understand the way it is usually used, immersion is a successful transfer of consciousness from one world to another.
It is often implied, that in order to immerse in one world one must forget the other.
I believe this is false.
The logic behind the regular reasoning is that in order to have immersion, we have to have two worlds. In order to have two worlds, we have to have distance between them. With a distance set, our fixed-form consciousness can travel linearly along the path set, and the length it can travel is a measure of immersion.
There are plenty of things wrong with this reasoning, but first we have to recognize that the immersiveness of a world is not an intrinsic value: it depends on the self it relates to.
Secondly, consciousness is not fixed-form.
Instead of basing the immersiveness of a world on distance, we can base it on flux. If we make it so that things flow nicely between the two worlds, immersion does not require forgetfulness - on the contrary.