Awwwww, Karen, thank you. That is really sweet!

babolaypo65 - you are an instant hit with me! For some reason, I have no idea what, the word "lurk" is one of my favourite words of all time! (Am I being weird again or do others have favourite words? Lurking, lurked...just lovely to say!! Not enough people use it so thank you!)

You seem to have a pretty good handle on what is going on with your Scottie. The danger is that it can become a habit if it works often enough for him and you may end up with a bit of a bullly. Even although he is small the breed has such a big heart and such a huge personality that power can become a drug for them and they end up thinking they are Dane sized!

I would suggest you get prepared at home. Get him into a game - fetch with a tennis ball or rope is ideal. Start winding him up before you get to the park so that he is focused on the game before he meets the other dogs. As you reach the park hide the play item in a pocket or behind your back. Produce it again as soon as a dog you are not sure how he will react to approaches. Training a signal for the game is really useful too - so every time you play the game you blow a whistle for instance - so you have an instant attention grabber.
Only try this if you are confident that it will not end up with him fighting the others off his toy.
If that is going to be a problem, and even if it's not, then try to arrange with the other people that visit the park to meet before letting the dogs off the lead. All the people get to say hello to each others dogs and the dogs get the message that the alpha of each pack sees it as safe and acceptable to be with each other.
If you could get a few to try some training together as well that would be great - fun for you too!