I'm glad to know I'm not the only lunatic out there who thinks her animals understand. When Gonzo, the big blue cat I had, first moved in with me I had an awful time keeping him off the counters. I used a water gun, mousetraps, sticky paper, you name it, I tried it. Finally, in complete and utter frustration I sat down face to face with him and explained that I didn't walk on the counters, and he shouldn't either. He never got on the counters again.
I never can seem to get my animals to use the standard commands. I did exactly the same thing with Bimmer that you did with Maddie, only it was coyotes instead of another dog I had to worry about. He knows when I say "now" it's important and he high tails it in.
I had to give up on calling the dogs years ago. I don't have a very big yell, so on 60 acres, each of the dogs has a different whistle. Instead of "sit," they both respond to "where are your manners?" I can't take any credit for that, Bimmer just did it on his own one day when he was being rambunctious and I asked him if he had any manners. Shiva's learned it from watching him. They're also good about plopping down when I snap my fingers. My Mom's rat terrier does "sit" for her, but for me - I have to tell her to park her little butt! Bimmer's version of "stay" is usually just me holding my hand up. Shiva knows what "don't even think about it!" means. She's also learning, "no surfing" now that she's so big her head is even with the top of the kitchen table. She also figured out what "drop it" or "gimme" was all about in a hurry; we're always having to take something away from her. She doesn't chew things up, she just carries them around. Somehow I doubt she'll ever go along with the idea of "stay." She thinks she has to take every step I take; she hates to let me out of her sight, which has made some for some fairly interesting showers!