Totman 199, 276 on Heike Monogatari and setsuwa 

The connection is not very often made  a connection between the Heike and earlier Gunki Monogatari (at least two of which were in literary kanbun and meant to look like historical chronicles rather than tall tales) would probably be more apt, and much more readily found in the best sources for this field. However I'm not sure  I'd rather see a direct quote from Totman before simply removing the sentence and replacing it with a comparison Donald Keene and I feel would be more apt.  (聖やや)