Recently I've ran into this issue, where I couldn't get the relative position of a selection in a Simple Object when using the default syntax. It returns [0,0,0] for all of them, but they don't have all the information that I need either.
Personally it's a blocker for me, because the algorithm that I wanted to reuse in my mod (BettIR) relies on that part working. The idea was to find the position of a particular proxy in the weapon model by spawning a simple object with the same model, getting the mentioned information from it using them for further calculations and functionalities.
If this command worked and if it returned information consistently for all selections and LODs, it would make a big difference.