Not sure if a tC has them, but if it has bumper shocks & the saturn did to, maybe that took the big part of the impact. Also maybe you thought you hit him faster then you did, most speedos take a few seconds to catch up when you are slowing down real fast. If the paint even damaged then I would wager that the real speed was less then 5mph & the guy let off his brakes at the momeny of impact to help absorb some of it. A 30mph hit would normaly at least cause a fender bender. Also Saturn pannels are a funky plastic that gives a little, when hit they give, but it can only give so far & in most cases its only like 5mm of give I think.