Don't be too hard on Gary Mack. He only showed one or two videos before getting to the Bell film, and both showed the corner of Elm and Houston. I went to the museum in 1995, chickened out, and left. Came back again in 1999 before I got my PhD and moved to Pennsylvania. That's when I spent time with Gary. Bob ? (I don't know his last name) did the first "oral history."
I found some differences between my first oral history and the latest interview. First oral history "I could only see grey burst from his head. I couldn't see blood, but it sparkled in the sunshine."
Last interview. "I could only see grey blast out of his head. I couldn't see red blood or any sparkles." I'm sure there are many more. To that problem I say, "memory is a bitch." It comes and goes. The human brain just doesn't work like a computer.
My favorite description of memory comes from Mary Carr.
"Memory is a pin ball in a machine.
It ricochets between image, idea,
fragments of scenes, stories you’ve heard.
Then the machine goes tilt
and everything stops."
So forgive witnesses whose 'story' changes from time to time. We do the best we can. It was 62 years ago.