Rolling our eyes is a Rhino method of dealing with Situations which defy comprehension. Alternatively, We use the Shrug. Both gestures have a range of expressive intensity.
We also use the two systems in tandem, including crescendos and rhythmic nuances, sometimes enhanced with oscillating snorts and pulsing huffs. Ancillary responses can also include tongue-clicking, toe-tapping and jaw-grinding.
When the Muttering begins, everybody heads for the hills.