Make it fun for the dog.
For one stop running so many damn marks in one day. Next ease up on the distances. Go train on some in cheaty water marks alone and see what the result is. It sounds like everything is a setup and not enough go get ums. start with shorter water marks and eliminate the cheat for a bit.
Are your no-goes on land, water or both? Have you done any force to a pile on land or in the water? If so I would suggest sending him on back!! I might also do a little pile work prior to running marks to get him ready to be sent on BACK. I would also take all factors out of the marks. Marks should be nothing but run pick something up until you are comfortable that the no-go issue is gone. Complicating the marks will complicate the no-goes..
I ponder over this over night, Here my 2 cents. I think that she is wanting to cheat and when you don't let her she no-goes. I would put her in some more open water, vary few factors ( Entry to be vary easy ) for a few days. Make it light one or two retrieves and maybe twice. If everything goes good. I would go back and start my cheating portion of my training, from the beginning. Or wait for while first and then do them. She is still vary young.
To me it sounds a lot like it is a pressure issue, probably created by the misuse and overuse of the E-collar. If you read he is going to no-go, don't send him. Rethrow the bird and try to improve his attitude. Don't send the dog when you feel failure is going to occur.
I truly don't feel a collar correction on a no-go on marks is the solution. Forcing to a pile is training for blinds. Marks should not need force to make the dog go. Marks only need drive and "want to" to make the dog go. It sounds to me, and I have not seen the dog, that the force/pressure used in marks has/is taking that "want to" out of the dog and replacing it with fear. This will likely be an issue that will continue to pop up throughout the dogs career. Do everything to keep all marking sessions positive and successful for this dog forever. That doesn't mean not to introduce concepts, it just means don't overwhelm the dog with too much in marking setups. Make sure he understands what he is to do and let him do it.
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I agree with others that you are probably digging a hole with all of this pressure, emphasis on cheating marks, and the sheer number of marks in a day.
There's one additional factor no one has mentioned so far. Your dog does better with wingers than with launchers. Could she be having a problem with echo? Her reaction as you describe it fits with that of a dog that is confused by an echo.
I can easily imagine that she has been confused by an echo in the past, and may associate that confusion with lots of collar pressure with either the launchers, the training group, or the location where you all get together.
I wish you success finding a way out of this repetitive pattern.
Launchers are hard to see at a distance. Quit throwing marks from them unless the marks are ridiculously short and easy to get to. Wingers at 300 yards are hard to see unless you have excellent bands and there's a ton of ribbon on the bird. Throw more (or only) birds, especially flyers or clipped wing pigeons. The last things you should be doing with a dog that no-goes are cheaty marks or multiples.
In my experience, it seems that the problems that took longest to overcome we're the result of too much pressure, not the other way around. There's a tendency to increase pressure to get quicker/better responses. Sometimes it works counter to your goal.
when we went over to work young dogs and he did really well it was a big body of water and we were just cutting corners. no re-entries, or any majorly technical aspects.