Hi, thank you <3
The intended rules were hoenstly as you said last: Letting players play as they see fit.
If you want my opinion though, you wouldn't need to get close right at the start, the progress bar helps with controling, so you can push a little bit more at the very end before a stop for example.
If you're close, I'd think slowing down or even halting for a few secs to avoid going too far is better, makes it last longer, more fun! Kind of what I'd do to a partner, so you can think the trainer would do that too if that makes sense!