Do you use the traps that run into the water on a one way ratchet?

In college one weekend I went with a friend on his trapping line route. He used that kind, I though it pretty clever .
Beaver steps on trap then bolts into the water, trap ran down a cable into the river, and beaver was safely chilled and hidden from predators till we came along..
Back then I think he said he got like 80 cdn per pelt.
That was 1987 though.