Our opinion:
Stop giving treats, cold turkey for basic commands and obedience. You will always be tied to treats if they are used for anything other than.........treats.
Defined: Treats are something, such as one's food or entertainment, that are paid for by someone else.
Let me explain, if I may (and if I am able in writing).
Your dog in his/her action of obedience is making a payment for the food, therefore, it is not a treat. But many will state that the food is truly a "reward." Reward being a positive reinforcement for performance of a desired behavior.
But here is where is gets tricky. Think like a dog, not as a human. What is food to a dog? Food is a biological need. Food as a reward creates confusion in dogs. The dog thinks he is able to get more food (meaning better survival) by performing desired behaviors.
This is why a dog will run up to you and automatically sit, or automatically dance or beg or whatever is the best means of receiving food: survival.
You have the ability to take your companionship with your pet to a higher level, by building a relationship without the use of food. Use a bright smiling face, welcoming pats on the head and soft spoken words of encouragement and care for positive encouragement, and I promise you will have the best fellowship you will ever have with a dog. And shelties do this best because they are so highly intelligent.
This is not a popular opinion, but we use no treats or rewards of food in training. In training they are learning their place in the grand scheme of the world and what is their relationship to you. When we are all just sitting around in the evening and everything is relaxed and nothing is going on, the dogs will get a "treat." A food treat paid for by us out of our good will.
Again, this is a good subject and must be discussed gently because we are working on inference and we are making our decisions based on opinions.
I have heard of this type of training. It's used with working dog environments a lot. I have seen some VERY amazing dogs that have been trained like this. I wish I had the time and training to implement this.
For me and the time and background I have, I'll use treats as currency to train behavior.
Imagine me trying that!!!
But I stopped treating at 8 months after using the clicker. Now it is just that, a treat once in a while.
. Megan will do anything for me when she has a treat to work for and it made it harder for her to listen when she had no treat. It takes a little longer to train somethings, but in the end it was better, for us anyway. I stopped using them during training and simply do the verbal accolades and physical affection. 
