It always helps having such an obvious finish line I think, that you can see the majority of the time.
When you longer than 400s on the road, you're begging for the end without quite knowing the exact spot.
Easier to programme your watch when you're not on a track though. As like our local mate who does his "Mile" reps on the track. More like 1550metre reps, the garmin doesn't like to work in small ovals.