>I fully agree about the philosophy, but I'm not sure how Zorder() could control instantiation order generally, when objects are added to screen with all having same default Zorder of 0 at design...it must either be tab order or order of object-adding that controls instantiation order (of same-level objects)...

It's definitely not tab order that controls instantiation, after a little testing, we can rule that out. When Bring Front/Send Back are set, it alters the record order in an scx. It's not really "Zorder," as such, but something kind of similar...

The order in which objects are added is the default instantiation order (at same level), and this can be seen by USEing an scx...