As we already see people put Till's cabs on almost everything, they should know to be careful about doing so.
If they are doing it by ear then no need to be careful - all that matters is how good it sounds!
However the geek in me would like to hear someone do the following (out of interest):
1. Profile Amp A & Cab A and Amp B & Cab B
2. Within the KPA swap the cabs - creating profiles of Amp A/Cab B and Amp /Cab A
3. Swap the cabs in real life
4. Then do an A/B comparison of the "real" swapped cabs v the "KPA" swapped cabs.
I think what we are learning is that the way the KPA "extracts" the cab is not flawless, but hey, the tone is what really matters, and for me the cab swapping ability is really an optional extra.