Well, a hand held stopwatch watch only reads to the one hundredth of a second.
If they stopped the watch at 4:17.99, the result would be entered as 4:18.0.
And if they stopped the watch at 4:17.91, that would also be entered as 4:18.0 in the results.
4:17.90 would be entered as 4:17.9.
The point of the thread is how do you say a mile time to the second, if the decimal reading is above .49 in the official results.
The answer is still that you would say 4:17 if result was 4:17.98 and you’d not say 4:18.