I read this thread today, it's been a good fun read! Lots of good advice and interesting stories.
About transitioning to off lead at a distance: long ago I had experience training a Chessie for bird work, and a GSHP for field bird work. Different types of field work, but the transition from 6' leash, to 20' rope, to off lead, included a 'shock collar' that gave me a 200' to 300' foot 'leash', and made a big difference, especially for that madly enthusiastic pointer!
He needed to know that I could always reach out and touch him.
Now we have rescue dogs with very sad back stories, and a whole different set of issues, and I'm much less motivated to work hard at training. And almost all the local trainers are 'cookie and harness' folks, not what works for either me or my dogs!!! Just recently I found a trainer nearby who will work with difficult dogs, and is fine with the prong collar necessary for both of my doggies.
One from a fighting dog abusive situation, and the other was living in an abandoned junkyard until rescued. Issues, you bet!
Mary