I must admit that we have changed from saying 'No' to saying a deep 'Ahhhh' to Ozzy when he jumps up, then ask for a 'sit' and as soon as he's down and sitting again he gets a treat or a stroke and told 'good boy'.
After all, 'No' is just a word, but Ahhhh is a deep noise a bit like a growl just to make him aware that what he's doing is not acceptable, and, by and large it does work, and it usually stops him doing what he's doing and gives us an extra second to distract him with a toy or a treat.
I know it's probably not really the 'accepted' way to do things in the 'positive training' way of thinking, and I wholeheartedly agree that to ignore bad behaviour and reward good is the best way to go, but there are times when it is dangerous to ignore the behaviour and you have to stop a puppy doing something immediately, sometimes from a distance, and a loud, deep noise is the best way.
Just as an example - I was carrying a hot casserole dish from the oven to the worktop the other evening, when Ozzy leapt up at it - I couldn't ignore it as it was too dangerous, for me and for Ozzy, and as I had my hands full, I couldn't distract him with a toy - I did turn my back at the same time as I yelled 'Ahhh' at him, but he did get the message and neither of us ended up getting burnt - to my mind that was the object of the exercise.
It's just another 'tool' in the box of tricks to help Ozzy become a joy to have around, and not a nightmare.