272RL slide topper
I just do what your dealer suggested. Most times only leave the awning out past the slide about 4 inches.
I only extend awning fully when I'm at the site and retract to the slide covered position when going away from the site. I never staked it. I considered this layout as a bonus since I only put one slide topper on the opposite slide room. I've always had slide toppers for the usual reasons. No sweeping, cleaner/drier, cooler, quieter(except when windy).
I never change the pitch and let the weight of the water, when raining, dip the awning as needed to dump the water.