A dog trainer whom I shall not name gives training tips on the internet. This week's tips tell you how to establish yourself as the pack leader and this is tip 2 out of 3 of his basic tips:
Tip #2: Spit in your dog's food. This sounds disgusting, right? Instinctively, the most dominant dog in the pack eats first... which means that his scent (saliva) is on the food. The subordinate dogs in the pack can interpret this as a form of marking, thus you are saying, "It's not automatically your food! It's my food, but I'm letting you have some, because I'm more dominant than you."
I must admit this is a new one on me. Definitely a different approach on a par with biting your dog when your dog attempts to nibble your ankles. Not sure I agree with either. Any reaction from other dog trainers out there?