That's a slamming post, AgedHorse!Except that it doesn't correlate in the least bit to damping factor. I can give as many examples of amps with a lower damping factor as with a higher damping factor when it comes to the PERCEPTION of "slam" (whatever definition may be assigned).
IME, it's more a part of the voicing than it is anything else. The problem is PERCEPTION, everybody perceives this a little bit different.