"Those french splits are very
>inaccurate. If you study them, you'll see they
>suggest both Fredericks and Johnson *accelerated*
>in the last 50m or so. Quite impossible,
>considering the race. In fact, here are some
>simulation results I've done on that race (Sim.),
>compared with the french ones (Fr). The last
>column is the differential between the two times.
>Note that they're all reasonable (within a few
>0.01s) except at 146.42m, where the differential
>rises to 0.30 seconds!
Split Fr. Sim.
90.00m 9.29 9.26 -0.03
>m 10.13 10.12 -0.01
110.00m 11.00 11.01
131.14m 12.93 12.89 -0.04
>13.75 13.71 -0.04
146.42m 14.57 14.27
158.56m 15.42 15.38 -0.06
>16.27 16.23 -0.04
176.84m 17.12 17.09
185.98m 17.97 17.96 -0.01
>m 19.32 19.32 0.00
I have the explanation of that big difference!
The source is quarterly AEFA Spécial Atlanta n°143 (1996). The analysis was done by Jo Maïsetti (who coached French 4x100m in late '80s-early '90s).
For taking splits, he used the marks for 110m hurdles noticable on the track. The space between them is 9.14m, and if we start to count from the 200m start line, the lines are at 112.86 (2nd hurdle), 122.00, 131.14, 140.28, 149.42, 158.56, 167.70, 176.84 and 185.98 meters.
So Maïsetti took times from a slow motion tape (i think it's the film taken by Jacques Piasenta) at each marks.
In the magazine, a typo mistake was made, and it was written 146.42m instead of 149.42m. The fact is that Maïseti used in his calculation the right 149.42m, the magaine did a mistake with the 146.42. So the split times are still reliable.
The problem comes from the fact that you took in account the 146.42m number in your calculation. That's why you find 14.27, as opposed as 14.57 for Maïsetti.
Maïsetti's numbers are quite reliable, i have myself analysed Piasenta video (100 frames/sec), and found same split times, with a 0.01 difference at max.
Concerning Mexico splits, Robert Parienté reported in his "Fabuleuse Histoire de l'Athlétisme" that Smith split time was 10.52. I don't know how it was measured.
As for X King splits, even though he finds the same 10.52, i'm perplex as the mid-race point isn't visible in the track (i have several footage of the race, including one B&W shotting the runners in perpendicular recurs at around mid race from the crowds.