A while ago I retrained Ronnie's recall command to a whistle instead of "come". Verbal commands are okay but in windy conditions often don't get heard at a distance.
The process is again similar in that you don't allow the dog to fail.
He had excellent recall to my old command so the process was - whistle (new command), wait 1 second and then "Ronnie come" (old command).
He would come back 100% of the time to his old recall so he was effectively never failing to recall to his new command. Within 4 goes he's coming back as soon as he hears the whistle knowing full well that it was a precursor for recall + the lovely treat that always comes with it.
Retraining a command can be really difficult but using this simple process it becomes easy.
Absolutely right Matt but you 'get it'. You would be amazed at how many people don't.
Every day I hear owners constantly calling their dog's name. It's as if they think the dog can't hear them. All they are actually doing is teaching him that he doesn't have to come when his name is called, and reassuring him that they still near by.
Poppy has already progressed to sitting on command with me standing a pace or so away.
I'm also in the process of teaching her to get into, out of, over or down from things when I tell her to. It's been really easy but its so worth while when you want to get your dog into a car, on to a table or over a fence. (Especially if they are as big as Ronnie).