One thing I have done different with these clones is that I have been watering them every 3 days at a minimum, whether the pot is light or not. I know the roots are not that well established, but the plants are heartier than a seedling of the same size, and they have a lit more going on than a seedling. So I let them drink what they can in those 2-3 days, then soak them again. So far so good.
That is what I eventually did to the GDP clone to get it to grow. Pot stayed heavy for a week, but the plant just stalled. didn't look bad, just stopped growing. I have seen definite growth spurts on these three associated with the feedings.