Let's discuss panniers, aka false hips! In the first part of the century women were still wearing their panniers in a pyramidal or cone shaped fashion. The cone morphed into a bigger, full dome shape, and in 1711, as one male observer noted in The Spectator, "The hooped petticoat is made to keep us at a distance."
This style soon changed into a more defined cascade, where the hooped petticoat extended from the hips allowing fabric to fall down at the sides. The front and back became flat, rather than a general dome shape. The silhouette was dramatic and the waist looked tiny. In 1739 you could find panniers reaching 2 3/4 yards in circumference (over 7 ft around!)
Passing through a doorway was not an easy task when donning an enormous hooped petticoat. Ladies would sometimes do an elegant turn to the left or right to glide through gracefully. Another option was to press down on the hoop and make it collapse enough to get through. But double doors were a welcomed architectural feature, making passing through easy and proper.
Another feature that was sometimes used to make life a bit easier for ladies of fashion, were curved banisters along walk and stairways. The slight C curve of spindles allowed ladies to reach the railing better, allowing more room for billowy skirts!