I went out and told them to calm down, and the husband (a big guy who must stand six foot three) came over, a little hesitantly. I assured him the dogs were harmless, and he came into the yard. Hero immediately jumped up and gently put his feet on the guy's chest, waggling like mad, and Impulse followed (because although he knows better, he will do what Hero does).
I yelled, "OFF!", but the guy said, "Oh, that's okay, don't worry about it," and put his arms around Hero, patting him. Of course, that was a cue to Hero to adore the new neighbor forever and ever. (Like the dog in Up: "I just met you, but I LOVE YOU!!!") He started bouncing higher and higher-- in front of the guy, because he knows he's not supposed to actually jump ON people very hard-- and the guy bent over and got smacked squarely in the mouth by Hero's happily bounding head. Hero didn't notice, but the neighbor definitely did.
Fortunately, there was no serious damage done. But let this be a lesson to you-- don't encourage idiotic, large, bounding masses of fur to jump on you. You might regret it.