Our dog, when out and about, and we have stopped to talk to neighbors or people passing in cars, will back up and sit down on our feet when we tell her to sit. She sometimes then, will lie down on our feet as well. The other thing she does is, if we are sitting on the floor playing with her, when she tires of playing, she will come over for some ear rubs and then turn around, back up and try to sit on one of our laps. I am not sure if she realizes she is far too large to do this, as she even tries to sit on my youngest daughter's lap!
My mom, who is a non-dog-owning, self proclaimed dog expert simply because she watches "The Dog Whisperer" seems to think she is trying to show dominance. Misty is not a dominant dog. I'd say she's about 75% submissive, but has a little assertiveness in her when it comes to certain things. It makes her fairly trainable, and she is generally a good girl with very few traits that we would change! She listens well, even when my 3 year old shouts out NO Misty!!!! Or Come Misty!!!! I've explained to my mom that I think it has more to do with her feeling like she is part of the pack and/or for comfort reasons than it being her saying she is dominant. I would think she would have other dominant behavior besides sitting on us. I have to wonder if my mom would still think she is dominant if she were an 8lb poodle crawling in our laps for a snuggle vs. a very TALL 50lb mixed breed.
Lisa, mom to 4 great kids and one darling puppy, Misty 
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