I appreciate You taking time to answer this very much.
This topic is not neccessary about the look through a particular camera, but more about the visualisation of the camera’s motion path from the side. And it’s about visualisation of motion paths in general.
Imagine, You want to position two motion paths relative to each other. You want, as You are working on one motion path, to have the other one visible. Unfortunally, as You deselect an object, it’s motion paths becomes invisible.
Or – to pick up the example of Brian Nishii – if You want to place some trees along the motion path of a camera, it would be amazing to see the motion path of the camera, wouldn’t it?
I’m afraid, Your answer would be that this is not possible in AE.
I hope, could make myself understandable.