I consider a leech pattern my 'go to' fly for 90% of my fishing, including both fresh and saltwater.

Bass (largemouth, samllmouth, spotted, and striped), pike, panfish, carp, walleyes, tuna, croaker, sand bass, corvina, bonito, roosterfish, dolphin (dorrado), barracuda (plus a plethora of odd saltwater fish I didn't take the time to identify), one confused baby sailfish, and trout too, have all responded well to my 'leeches'.

If they aren't 'popular', I have no clue what fly is, at least with the fish. I find they work as well as, or better than, a clouser in most situations.

If other fishermen don't 'use' them more, that's just fine with me...

Buddy