I taught my pup stay and proofed it well, then didn't start him on birds until he was about a year old. So, he knows he's not allowed to look, sniff, move, whine, etc. A stay is a stay. He can do it while laying, sitting, and standing. He can stay while balls are rolling in front of him, treats are thrown inches from him, kids running around, dogs are retrieving in the next ring, pomeranian puppies are running amok, girls in heat right next to him (wearing pants, of course), next to strange dogs, etc.
The bird and gunshot is way harder, I will admit, but he does it. Did it the first time asked with a live flyer. Believe me, I don't need to tell him twice when I release him! I did all the obedience first, and lots of it, which has made the field training easier. Just went a different route based on my interests I suppose.
So, what about obedience and proofing the stays? Putting a few months into that? I put a solid year into him before starting him on birds.