I share his frustration. There are some data structures set up that record where the parts go to, but they are not accesible beyond click and drag. This is OK for small things, but when there are a large number of components to deal with or there are multiple similar assemblies that need to have similar explosions, having no numeric control is a pain. The increment only controls the step size while the item is being moved, but it doesn't allow confirming where the parts were placed.
Most often it's when I want to move a subassembly, but miss a click and get the largest item and then have to redo the whole mess.
It's been interesting to use it for assemblies that are dismembered to show a shipping configuration, rather than creating a separate assembly and ensuring they both contain exactly the same items. Even if it was available in WF5, I would not enjoy building family tables that included variant assembly constraint sets to do this - because sometimes it is parts of subassemblies that get divided into different groups.