our dog wets with little stimulation

Question
We have a 8 month old neutered male border collie/shepherd mix we got from a shelter one month age.  Housebreaking was easy however! --he dribbles at times.   When I do the "go sit down command" and he gets up before being released I will put a finger under his collar as per "The dog Training for Dummies" book and take him back to his go lay down spot but that causes him to dribble. (I figured that is submissive?)  However he will also dribble when he gets a little excited,for example, when my wife was working on "the go fetch" with a rolled up newspaper she would have him sit first and he would dribble before she threw the paper which I assume is excitement as he enjoyed doing this?    should I continue to do the go lay down as I have doing and he will "grow out" of the dribbling (we have hardwood floors and wipe up dribbling accidents with vinegar so we can handle that and we don't do the bad dog or get after him when he dribbles)  AS a FYI when we walk and we see other dogs he doesn't cringe or do submissive behavior with other dogs (or people)
thanks

Answer
This could very well be a problem he will grow out of but one suggestion when doing the "go sit down command" and you return him to his spot you should reward him with vocal and physical praise for getting there regardless how he got back there.  To increase your success on this procedure follow the ONE,TWO GOOD DOG! protocol by taking him to his spot(ONE) while you command it then praise (GOOD DOG) immediately upon reaching the spot(TWO).  Then walk away and let him follow and repeat the process.  Look for 10 to 15 reps of this in 3 to 5 minutes.  You may even have to lead him away from the spot but get the reps.  Remember that "stay" is a separate action and should be taught that way and then combined once they are both learned.  By doing this you will not only get the "spot" command taught but you will help the dog get over the "dribbling" as it won't be able to dribble every time and will become use to being physically returned.  If the dribble continues or worsens I would have a vet check it out just to be sure.  Need additional help feel free to call. Dr. Hogan  509-991-0385 until 10pm pacific time