I remember seeing that Cook's Country recipe, and I thought that it looked like too much sugar - something many recipes seem to have, for just a basic dip sauce.
The one I use has some water in it - 1/4 c each lime juice, fish sauce, and water, plus 2 tsp white rice vinegar, which gives it that unique flavor. Only 1 tb sugar, and one large or 2 medium garlic cloves, crushed and minced, and one large or two medium thai peppers, minced. If I am only using part of this at a time, I'll make it without the garlic, and add a smaller amount of garlic in what I'm using, since raw garlic changes flavor, in storage.