If you have the best soundstage conceivable in a home setup, and then you move that system to a closet or the bathroom, does the soundstage change? Of course.
If you have the best soundstage conceivable in a home setup, and then you drop your amp from the top of a tall building, does the soundstage change? Of course.
More seriously, demonstrating the existence of one effect does not necessarily demonstrate the non-existence of another.
Mornin!
John