was pulling i think 400 foot of cable / rope / straps / chains. and hooked it up behind the S10 blazer at the time. and pretty much doing what you are thinking of doing...
it pulled clear down the a couple sides for sure of the moss. but the end result was i could never drag the moss / weeds up and out of the lake. the end result was most of the crud decaying right at the corner in one spot. i ended up grabbing a lot of 1" size fish, and a few larger fish size about size of your hand when fingers are spreed open. that never made it out of the moss in time. it ended up turning into a big stinky mess. if i had a tracked mini excavator with a hydraulic thumb or some form of wide grapple setup on it, that would been awesome cleaning up the mess up in the one corner.
--tines on a de-thatcher, were a pain in rear to clean out. with a couple hundred pounds of moss (more so the wet water the moss held within it) dry couple day old moss = light. not moss ya just pulled out. i ended up destroying a some cables and chains. due to i got so fed up. i just began yanking the unit out of the mass. and letting the moss rip apart little by little bit.
--once i got all the moss in one corner i simply could not pull it out. just to heavy and moss was breaking away once i put enough force on it.
--i ended up having a couple large aluminum 1/2" thin wall pipe bent up. it was for "large hooks" to hold garden hoses and like on the wall. that seemed to work the best with moss. vs the actual tines on the de-thatcher.
2 to 4 weeks later everything i dragged down the edges... grew right on back *big frown*
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if i had to do it over again....
if i had a large enough cable winch, to wrap a few hundred feet of cable on it. that would of been awesome for me. granted winding up cable can be rather slow. but that is what worked for me. going to fast and i would skip areas of moss / weeds. going slow gives chance for the little tiny fish a chance to swim out of the moss.
--1/2" rebar bent and welded to a "trouble hook ( 3 fishing hooks put together for say catfish lures and like), purely guessing 2 feet long, then end bent into 1 to 1.5 foot diameter hook end.
--a triangle frame with a sled down the center, to keep the point up.
--the trouble hooks would need "quick connect loops" so i could undo a single hook and pull it out much easier if it got tangled up.
tossing the dethatchor out along with cable and everything was not an easy task. if you had a "boom pole" attached to FEL so you could some how attached it and drop it off out a foot or 2 off bank edge would help. maybe just a cable or rope, that was tied on to FEL, ran down to the thing, then back up to bucket. so ya not sinking in mud trying to unhook things.
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last minute thought. maybe a couple extra hooks instead of 3 hooks combined into 1. maybe 5 to 6 hooks combined into one. the ) shape of the aluminu hooks i had. seemed to work great. if i was able to keep the thing pulling correctly. the very outer edges of hooks would cause the moss to build up in the center. and the outer edge hooks would just keep bring in more moss.
to note it. i did get to a point a few times were i just completely over loaded the setup i had with the de-thatcher and alumin hooks. and i just had to reel it in per say. clean the mess off. and then go back and toss it out again.
