Right. Changing that setting affects the behaviour in some cases, but it doesn't seem to stick. It's probably not of any direct relevance.
Now the most consistent behaviour I'm able to observe is this: If an item is selected in the top view AND no item is selected in the bottom view, then attempting to sort all files using the column header doesn't work (it instantly reverts to the album grouping). It works fine if an item is selected first. Maybe that's why refreshing seemed to make a difference. And this is for "Categories" views only; the problem doesn't seem to occur in "Panes" views.
Now that description isn't entirely correct. I'm leaving it that way because it's the easiest way to "get" what's happening. But the problem doesn't seem to be that no
item is selected—it's that the
lower view isn't selected. Clicking anywhere in the lower view that doesn't cause an item to be selected (e.g., on the title bar, or between groups) will select the view. There's no visual evidence of this, and the item in the top view will remain highlighted—making it appear it still has focus. But sorting all files will work after doing this.
I'm not sure what all this means. Maybe the "bug" is that clicking on a column header selects the column and displays the context menu, but fails to change the focus to the lower view.