My suggestion is to update the Description for the Mobile Update to the G4 Technique to stress the requirement for keyboard interface (2.1.1) support.
G4: Original Description:
Description
The objective of this technique is to provide a way to pause movement or scrolling of content. If the user needs to pause the movement, to reduce distraction or to have time to read it, they can do so, and then restart it as needed. This mechanism can be provided either through interactive controls that conform to WCAG or through keyboard shortcuts. If keyboard shortcuts are used, they are documented.
G4 New for Mobile: Suggested changes..........
Description
The objective of this technique is to provide a way to pause movement or scrolling of content. If the user needs to pause the movement, to reduce distraction or to have time to read it, they can do so, and then restart it as needed. This mechanism can be provided either through interactive controls that conform to WCAG or through keyboard shortcuts. Standard keyboard interface accessibility is always required (under 2.1.1), and if non-standard keyboard shortcuts are used, they are documented.
Katie Haritos-Shea, 30 Sep 2014, 15:17:19