Thanks to all for some very good information. Occasionally resurrecting a venerable thread is a very good idea. Looking at Mark's squimp and Boot's "this guy", a major difference I noticed is the orientation of the fly. Boot's faces the line and rod, Mark's faces away. So on a retrieve, Marks moves butt in front, Boot's face in front. Which way does a shrimp move through the water? Probably doesn't matter that much, just curious.