Existence of a significant speed difference between PAD and trackpad in the email task

Ascertain whether the Preview-Accept-Discard (PAD) interaction yields a statistically significant difference in task-completion time compared to trackpad use for the email "reply-and-send" task under comparable experimental conditions.

Background

In the email mockup experiment, participants performed a simple reply-and-send sequence either with PAD or with a trackpad. While PAD reduced motion, the paper intentionally emphasized feasibility over statistical inference and reported that a significant speed difference could not be determined.

This leaves unresolved whether PAD is faster, slower, or equivalent to trackpad usage for such tasks, motivating further controlled studies with adequate power and inferential analyses.