This maybe a bit hard to explain and I'm just looking to understand something here.

I use a default geo object with the box, put a sin expression in TY and run the animation.
I then go to the geo sop space where I see the box moving up and down, because the world space view flag is on. I have the construction plane viewable.
Here's the tricky part, if I turn off the world space view the box stops, obviously because there is no translation happening in sop space, if I turn on world view again the box resumes animation but depending on when I do this the world origin has changes position.
If I continue turning on and off world space view, if I time it right, I can have the box accumulate a TY location relative to the construction plane.

The part that is troubling is that the construction plane doesn't reset to the new 0,0,0 location of the box's origin if I turn the view off and on.
This doesn't make sense to me.

Hopefully my description is clear and someone can explain this to me.

Hahaha

That's funny….

Yea the camera transform its definitely accumulating on the construction plane.

Simple repeatable steps.
1. Create a geo in /obj
2. Put sin($F) in ty of the geo
3. Go into Sops (the geo)
4. Turn on the construction plane
5. Hit play
6. Start hitting “e” in the viewport (view everything toggle)

I'm not sure how Houdini handles the viewer xform when you are in SOPs.
I suspect when you have everything turned off the viewer is in the same space as your object. By turning off and on the “view everything” mode you are accumulating the xform on your camera.

* all this only applies if you have <no camera> as your camera or if your camera is parented to your object in some way.

Your right, if you do the same experiment viewing through a camera it does something else.
The camera zooms in and out depending on when you switch between world and sop space. The zoom accumulates as well.

I'm not so much trouble by that stuff, what's trouble is that the construction plane doesn't reset to the “new” 0,0,0