This is actually pretty sick but I cant seem to turn off the Instant movement option
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I had the same issue. It looks like the UI for deceleration handle is drawn on top of the Instant movement checkbox, so if your deceleration handle is all over to the right, you will not be able to click the Instant movement checkbox. So what you have to do is to move deceleration handle to the left, disable the checkbox and then move the handle to the right again.