Yes. In the committees I've chaired, I've generally directed the clerk to go to the witnesses and suggest that if they have opening comments, they have up to 10 minutes. That's generally what I do. And I suppose if this motion were to carry, she would go on my direction--I don't think there's any rule that she has to go at all, at least that I know of--to suggest to the witnesses that the group would have up to 10 minutes, and one person could speak or you could conceivably have a group of 10 people. That's the way it would work.
That's my interpretation of the clerk's role.