When I add a marked item as a child and then immediately use Alt-Left to promote it to the level above (i.e. to make them siblings of the parent at this point in the grid), the marked item will often jump one slot further down in the grid (i.e. below the next item rather than the parent). If I do this with multiple items selected, the first item will appear below the next item, the second item will appear below the item below the next and so on.

 

To be able to use this method as a quicker replacement for drag and drop operations in / between grids, I would like to suggest additonal options:

 

- move marked items here as siblings (move to below this item in this grid)

- (and possibly:) move marked items here as children

 

Cheers