Used to slay big gills on small leeches ( live ) the ones too small for walleye. I don't see any reason those won't do the same. By the way the walleye didn't know they were too small and they gobbled them up also.

When I operated a bait shop I always had plently of little leeches as the fishermen wouldn't buy the small ones. The only way I could buy them was mixed. Might have to try tying your pattern as I haven't had live leeches for quite awhile.

Rabbit zonker strips also make a good leech imitation according to a lot of tying sites.