location dependent height is a one way command: it assumes that you will pass an obstruction and your speed increasing will determine when it is safe to lower again.
i find this very useful in many guises eg approaching a road with a run of sleeping policemen (English name for speed bumps!). I can raise the car and it will only lower again when I have a flat enough road to speed up again so it avoids the need for multiple presses to cope with each bump.