Recently on an episode a new shower pan was being installed using a different technique. The mud was distributed in the pan and then a scored cement backer board was placed on top of the mud and the tile layed on the board. The question is how do you achieve the 1/4 per foot slope to the drain with this process. It looks like an easier method than trying to screed the mud and troweling it smooth, but in the episode they cut it short and didn't show how the slope was achieved. Is anyone familiar with this method?