I think we have to expect and appreciate the slow weight loss we get with the SP Program. In her book, Dr. Schwarzbein says that 1 pound a week is appropriate. Her plan is not really about weight loss, but about becoming healthy. That's why I'm doing her plan rather than the excessive/scary (to me) Atkins diet.
More than anything else, I expect my fasting sugar test to be normal in 3 months when I retest (two months ago it tested at 138, 125 is the top of normal, 200 is full-blown diabetes according to my doctor).
I know my initial weight loss is the usual "water weight" loss associated with any plan that causes you to lose weight. It's not really true weight loss. I am expecting to drop no more than 1 pound a week once my system has adjusted.
Also, the closer you get to your optimum weight/configuration, the slower it will go, and you will appear to plateau, because you are consuming nutrients at a level that more closely matches your optimum level.
Think of it this way, when you weigh a lot, you require more "calories" just to maintain that weight, so if you eat the food that would sustain you at your optimum weight, you will lose weight. As the amount of calories required to keep you at your current weight drops with your weight to more closely match that required for your optimum weight, your weight loss will slow.
That tends to be the reason most people get discouraged with diet plans. They expect to keep up the same rate of weight loss all through their diet.
I expect it to take me 2 or 3 years to get to my optimum configuration, whatever that turns out to be. But I am going to feel healthy and satisfied as I do it, and I will not have to relearn to eat when I get there, because I will have been eating for my optimum configuration all along.
Finally to answer your question: I think you should go slow and easy. I had a day when I didn't eat the carbs I should have and I felt awful. I had some cantaloupe and felt much better. Since then I have made sure I got the carbs I need to keep feeling great. To me it's better to take it slow and not stress my body than to see a quick drop on the scale.
Hope this helps,