The math is pretty straight forward:
0.75 Seconds is approx 0.002 hours - 286A X 0.0002 = 0.06Ah's
1 second is approx 0.0003 hours - 286A X 0.0003 = 0.086 Ah's...
2 Seconds is approx 0.0005 hours - 286A X 0.0005 = 0.14 Ah's
3 Seconds is approx 0.0008 hours - 286A X 0.0008 = 0.23 Ah's
4 Seconds is approx 0.001 hours - 286A X 0.001 = 0.28 Ah's
5 Seconds is approx 0.0014 hours - 286A X 0.0014 = 0.40 Ah's
Keep in mind that the test at 286A was a 44 HP four cylinder diesel with an actual physical battery temp of 32F. Starting currents are highest with cold engines and cold batteries.
If an engine is physically cranking for more than 5 seconds, even when cold, there are issues that need to be addressed. Most engines I measure have a start duration of under 2 seconds. The range of 0.75 - 1.5 second being the most common loaded to unloaded duration.
Even if we gave that Universal M-25 shown in the video 3 full seconds to start, which it was not, and we rated it at full in-rush for the entire starting duration, which it does not do, it would look like this:
3 Seconds is approx 0.0008 hours - 198A X 0.0008 = 0.16 Ah's
5 Seconds is approx 0.0014 hours - 198A X 0.0014 = 0.28 Ah's
Of course in this example we are using absolute worst case scenarios, that are not true, and we are still at just 0.16Ah's for a 3 second start and 0.28Ah's for a 5 second start.. The reality is that the average cranking is far less than 198A and this motor starts in less time..
This is the entire test done on that particular engine.
Resting Bank Voltage, Tested CCA of The Bank, Rated CCA of Each Battery, Battery Case Temp
Cranking Current Over Duration Of Start (this represents 0.75 Seconds)
Voltage Performance During Starting Eposide
Average Voltage During Starting Episode, Average Current During Episode, Duration Of Start Loaded to Unloaded, Circuit Resistance