I have only ever seen this dance twice, and both times it was by the Ichiyama Kagura Group at an Omoto Kagura performance.
The dance is performed by a single dancer, and begins with the rolled-up mat in one hand and bells in the other. Later the mat is unfurled and the dancer steps backwards and forwards through it then wraps himself in it and spins around. As the dance progresses the pace increases.
The dance originates from Sada Shrine up in Izumo, where the dance is performed once a year as part of replacing of the mats in the shrine.
Sada Shrine, one of the 3 most important shrines in Izumo before the ascendency of Izumo Taisha in the late Heian Period, is the home of Izumo kagura, one of 3 or 4 styles of kagura in Japan. It is generally believed that Iwami Kagura is derived from Izumo kagura.