As a member of the foundation, Greg is subject to the same rules and functions as everyone else, but the question is still valid.
As the owner, Greg could retract the bylaws completely and unilaterally; an action that would essentially shut down the RESF and be a very public signal to the community that something unanticipated has happened which jeopardizes the Projects (e.g. Board manipulation, takeover of control, etc.).
Contingency planning is critical to the long term success of an open source project, and we all take that commitment very seriously. Greg’s role may not always be that of decision making, but he will be there to resolve any unforeseen complications in the RESF and to ensure the long term survival and community control of each of the hosted Projects.