Something that I didn't notice any runs implement, so I wanted to make a post about it here. I noticed the timer adds up between levels as points, in intervals of ones, then tens, then hundreds. So with this in mind, it's actually faster to end the level with either 100 seconds, 10 seconds, or 1 second. This can easily be achieved by holding the "abort" button midway through each level, which makes the timer tick down super fast.
Here's a video as proof: https://giphy.com/gifs/STTSxbMMX3LSQpiNU7
Seems that you'd optimally want to route the timing of the abort button to leave you with 10 seconds left, as you would lose a little less time if you made a small mistake. For safety strats, end with 100 seconds probably. It seems like it's not a lot initially, but if the runner does a lot of them successfully then it could save a decent chuck of time.