Getting our second Chessie pup the first week of December. Didn't get the first one on birds early enough due to some health problems (not serious). We want to be ahead of the game this time. How soon do we introduce birds (ducks) to the new baby? I think the earlier the better, and do goose wings really help bring out the birdiness?
Hunt waterfowl/hunt tests/conformation and what ever else comes down the line.... My first Chessie, Rocket, was not forced. Working with a great trainer who does not believe in forcing Chessies. She has great instinct, but reluctant to pick up birds - she pulls out some feathers and mouths the birds. Haven't had her in a real hunting situation yet. That may be the ticket - get her out and hunt!
Pulling feathers and mouthing are normal responses for young puppies. You could try teaching a "taught hold" without pressure, then use this to encourage a better hold on birds.
If the dog is tentative about birds in a controlled situation, then it could just be worse out hunting. There, you will be less inclined to work through a problem if it crops up. This is how habits are formed.
You may want to rethink force fetch. It isn't just about getting a "reliable retrieve". It teaches a dog how to handle pressure, both mental and physical. The dog learns how to turn off pressure. It is a tremendous confidence builder. If you have any inclinations toward competitions, then I strongly recommend it. Once you get bitten by "the bug", your goals may change. Deciding later on that you want to do FF after all can be hard on an older dog. It's better to get those tools in the toolbox early on. Also, ff is a building block to a whole bunch of other training tools you will find handy.