Imo, this really is a major flaw of the new profiling concept. The reactive load presented to the output transformer of the amp changes with every cab. I did not yet make an approach to really compare the impact the different cabs have on the same amp when creating DI profiles. I only compared a cab as a reactive load vs. a load resistor. The differences on the DI profiles were huge. Maybe someone with highly different cabs could do a comparison on DI profiles? Like a "1 x 12 vs. 4 x 12" with different speaker types?
I wouldn't call it a "flaw". CK pointed that this existed and it's been on his mind for a while and is probably the reason behind this new technological innovation. Its HOW you use the technology that makes or breaks it's usage for your personal needs.
I think the main idea is to be able to go out full stack and DI to a stage cab and have them sound the same.
There are flaws for all systems and compromises. Fractal's owner pointed out that schematics don't show you actual layout and that magnetic interference of on-board components may affect the overall tone of a circuit board and cannot be modeled beforehand. So the same VOX AC15 over decades may have differing board layouts that affect the tone, or circuit components that affect the tone (we all know the arguments over differing Caps) and so your modeling can only model ONE particular sound you are comparing it to, or an idealized schematic that alters when done in reality.
So the Kemper approach is at least REALITY based and can be applied within seconds to approach YOUR own sound, whether it be differing components, layout, wood density, etc, etc. This includes impedance loading. At least NOW you can have an accurate separation of the Amp from Cab by a process of elimination, rather than an arbitrary decision. THAT was a flaw that CK spoke about, and now has solved.
Man, it's too early for such things. And I'm not educated in such matters. This is just a lay person's understanding. Is this what the Germans differentiate as kennen vs wissen? I know what a transmission is and what it does. I can't build or fix one, haha.