Here's my framed example of a timing slip from the Shootout a few years back. It shows that the timing is done on a single running clock showing elapsed times from the entry of the first light beginning of mile) to the second light (entry to the kilo) to the third light (end of kilo) to the fourth light (end of mile). Add up the first three times and you get the fourth one.
And by sleight of mathematical hand you can determine speeds from the first to second light and third to fourth -- like is shown here -- giving you those splits.
And, for what it's worth, has anyone got a SLOWER timing slip from a Shootout? I admit it -- 'twas a slow afternoon and Cook got on the radio and called out "Slim! Get on your pit bike and run it through the lights. There's nothing else going on!!!" And for further what it's worth -- while I was motoring down to the lights (quite a project at dang near 30 mph!) I did something that I think I can safely say that nobody else has done on the race course: I passed the Speed Demon. REALLY. Of course it WAS being pushed down the course for a photo shoot or something, but still -- I passed the Speed Demon when we were both moving.
And so now, by Stainless' reckoning, I must be, while riding the pit bike, at least, one of the Big Boys. Yippee-ZippEE WOW!
Okay, I'll go back to eating my cherry pie and glass of milk now.