I don't mind some treat training along the way. They eventually will do anything for you minus the treats. They work for example quite well when doing initial exposure to loud noises and eventually shotguns. I find starter pistols to be quite loud and prefer a shotgun.
The one area that I would strongly recommend is learning how to force fetch your dog. If you aren't comfortable doing it, then work with someone who knows how. Its uncomfortable for the dog, but it results in a fool proof retriever that will not be distracted. Looking back, its my biggest regret that all my previous dogs weren't taken through it. My new pup will for sure go through it around 6-8 months of age when he is ready.
The rest is pretty easy, just do a lot of bird exposure.
