I think I've never heard it said better. I like to think that I'm my dog's guide. The enviroment we live in can be confusing and prety dangerous for a dog. I make rules to keep us both safe and not a nuisance to others. To do this I don't need to physically dominate my dog or scare her. She loves to make me happy and the slightest disapproval in my voice will stop her.
Your mom is indeed a wise woman. Dogs are living with us for about 10 000 years and it would be very astonishing if they hadn't evolved and adapted to this very different life. Dogs do understand us pretty well. We should do them a favor and learn a bit 'dog' to be a really good friend.