all this discussion led me to digging up what good ol' alt.music.nin has to say about this stuff. At least the story about Trent doing it just for teh lulz seems to be consistent over the years.

is it possible to determine the date by their hair though? we've got plenty of Hate tour videos so we can just compare.

as for lee mars. He wasn't necessarily a part of live band at the time since we don't know for sure if they were on tour at the time. but he could've been just someone's friend, you never know all the connections. I was surprised to find that Nick Rushe (NIN keyboardist on Peter Murphy support tour) had a credit on Exotic Birds album, that was clearly done a couple of years before NIN.