Yea, I remember these tragedies, they were so publicized back then.
Back in ancient times, when I was a young'un, Kennywood NEVER checked restraints on coasters until they installed the Laser Loop. And even then, they just did a sport check to see if restraints were down, not necessarily locked. As we all know, today, it's a different story.
The only other restraints they really checked back in the 70's (which was really ahead of their time) was for the Kangaroo, Space Odesy (Scrambler) and Paratrooper. These rides had (and still do, minus SO, which is gone,) old brass latches that a lot of smaller kids have trouble locking themselves.
Most of the rides back then didn't have restraints at all, like the Catepillar, Calypso, Grand Prix, Le Cachot, Old Mill, and more...
Slightly unlrelated, I just heard Kennywood is updating the Log Jammer with seat dividers. (Back rest in the middle of the boat to divide seating 2 and 2 per boat.) Shame that the way we remember things gets ruined by a letigious society and stupid people's children.
I really need to get my classic videos encoded.