You made me curious so I dug into the paper. > For our final study, we selected a progress bar that featured Backwards Decelerating ribbing, as this was

You made me curious so I dug into the paper. > For our final study, we selected a progress bar that featured Backwards Decelerating ribbing, as this was slightly preferred over the pulsating behavior in study three. This was compared against a standard, solid color progress bar. The test interface, instead of simply recording participant’s preferences, used the responses to warp the duration of the ribbed progress bar (the solid color progress bar had a fixed duration to act as a control). Specifically, if a user felt the ribbed progress bar was faster, its duration was extended (to slow it down). Conversely, if the user felt the ribbing was slower, the duration was reduced (to speed it up). Equal responses left the duration unchanged. The goal was to allow participants to converge to a duration where they believed the two progress bars “felt” equal. (For an extended discussion on method of adjustment experiments,please refer to [3], “Difference Thresholds”). So I want to guess they were given some kind of interface that would let them decrease the speed in increments of 1%, perhaps.