I would think any bunch grass like prairie grass would create channels for water to go around the bunches. I have praire grass on the flats above my pond, but never thought it might be better than crown vetch as a steep bank cover...Is the amur silvergrass a bunch grass as well? The Crown Vetch does "lean" over at the end of the year, so I do have to rake out some of the dead areas each year. Might be an improvement to change it. My pond is totally contained by my driveway, so it would be easy to keep it in check.
