Dips and ceilings

Interface guidelines encourage designers to include shortcut mechanisms that enable high levels of expert performance, but prior research has demonstrated that few users switch to using them. To help understand how interfaces can better support a transition to expert performance we develop a framework of the interface and human factors influencing expertise development. We then present a system called Blur that addresses three main problems in promoting the transition: prompting an initial switch to expert techniques, minimising the performance dip arising from the switch, and enabling a high performance ceiling. Blur observes the user's interaction with unaltered desktop applications and uses calm notification to support learning and promote awareness of an alternative hot command interface. An empirical study validates Blur's design, showing that users make an early and sustained switch to hot commands, and that doing so improves their performance and satisfaction.