Bruce Felter told me many years ago the small pedestal mount made these impressions from being hit or dropped, which I personally find a much more plausible explanation. I mean how hard would you have to tighten the snares to achieve this? I've repaired my share and they all looked dropped to me $00.02
I'm inclined to agree with you. It wouldn't take much of a knock to cause a dent. Drums+gigs+beer can easily add up to damage.
FFR428 - this one's for sale. If it doesn't sell then I'll happily hold onto it. At least I can say I tried to sell it. I have had a long shelf put up in my drum room and I didn't think I'd fill it - it's now overflowingDOH