Good questions! Trixie is generally really good with other dogs, except for when she is on-leash. When I take her out and there is a dog across the street she starts pulling the leash and starts barking like crazy - it sounds violent. Most of the time when I bring her over to the dog, she's fine, but some times she sniffs and then again starts violently barking. Then I remove her from the situation.
She only does this on a leash, when I take her to the dog park or she plays with other dogs inside off-leash (even dogs she hasn't met before), she is totally fine, no peep.
When she barks like that, I usually make her sit down, or I hold her laying down on the ground until she's calmed down. I'm going to have to try the water pistol though, that looks like a great idea.
__________________  Trixie |