I've been watching Good Dog U - he believes in teaching 'no' as one of the first and essential commands. Not screamed in frustration, but quietly spoken as a cue to the dog to stop what it is doing. I have never used the command, it always seemed imprecise and I'd rather give a command to do something specific. 'Here' rather than 'no - don't chase the cat'.
But I think it might be useful for Dusty - a cue that says "That thing you are thinking about doing - don't do it."
They are re-building the road above South Newcastle Beach and have closed the steps off at the far end of the beach. Dusty ran up the stairs and under the barricade. I looked up from throwing the ball to Thommo to see her crouched ready to leap from a point ten feet above my head. I managed to run down to where the wall was lower and the sand piled a little higher and she followed me, landing her leap safely. A 'no' command would have been nice.
This evening, for a change, we went for a walk on Ash Island, choosing the path along the boardwalk through the mangroves. I'd walked Joel, Diesel and Thommo here regularly, but it was Dusty's first experience. Always, in the past, the dogs had walked along the board pathway to the clearing where there is a log seat and a grassed area for fetch games. But not Dusty. She leaped off the boardwalk into knee deep black mud, then despite my efforts to get her to stay, tried to jump up the metre plus and landed on her back - in the stinking black mud. I jumped down to get her and put her back on the boardwalk, but my shoe got sucked off in the mud. Before I could retrieve it, Thommo jumped down to see what was going on. I got him, muddy footed, back onto the walkway, found my shoe and hefted myself back up. Just in time to see Dusty preparing to leap off again on the other side.
A 'no' command might be useful.