I don’t need to speculate as I’ve done it just to see what would happen, and then again every other build to see if they changed anything.
When you load a Tri-Ax figure (Genesis, mil horse2 or clothing etc) the DUF file you used only holds a small part of the required data, the rest is in DSF asset files in the data folder. While that figure is in the scene DS keeps checking those DSF asset files as they are “live”, you see this when you spin a morph dial, there is a slight delay before the morph works, that’s the deltas being loaded directly from the asset file. Now when you modify a figure either by changing the grouping, the WM or the rig, then DS flags those changes as the figure is no longer the same as the asset file DS is referring to, so when you use “Save Modified Assets” DS already knows which asset file(s) it’s going to be replacing with the data from the scene. With morphs you can spin the dial and it wont get flagged, but change the path, change the name or even just changing the dial color will flag it.
“Figure/Prop Asset” writes everything in the selected figure/prop into the data folder, even if it’s an existing figure/prop like Genesis, the only way to stop it overwriting an existing figure/prop is to change the authorship data in the asset window (see pic), this will cause DS to write a second copy of the figure/prop’s asset files into the data folder, but into a different sub folder than the original that way they don’t clash.
I get the feeling this is why we still get “Genesis is loading morphed” threads, as the idiots have used “Figure/Prop Asset” to save their characters rather than the character or shaping presets they are meant to use.
As for the scene & subset, I haven’t had any reason to save WM/rig changes like that, I usually just use “Save Modified Assets”, I do know that it saves any group changes I found that out when I tried to help out with the supersuit debacle, so I assumed it would also save any WM/rig changes.