This matter of guiding a viewer's eye is much less important than it was in the late 1940s when sedans were taller than they later became, and often had slab sides to boot. Current SUVs are tall, so some sculpting is usually helpful when stylists try to make a boxy shape seem more graceful. But most sedans these days are pretty low and have nice proportions to begin with, so adding sculpting to their sheet metal is largely an exercise in decoration.
I'll characterize this sheet metal sculpting using the old term "speed lines," which refers to shapes added to the basic form of a car to make it look like it's going fast, even when at rest. Sometimes speed lines were enhanced by chrome trim, but often enough they alone carried the visual load. Below are a few examples of speed lines found on American automobiles from the 1930s, followed by such lines decorating some current sedans.
Speed lines here are enhanced by a secondary paint color. Most noteworthy are the lines along the top of the hood and the curved vent covers along the sides of the hood.
The Nash shown above featured a large number of sheet metal indentations with the appearance of grooves. One such line extends from the grille to the trunk. Another outlines the side window zone. And there are even grooves along the tops of the front fenders.
This Graham's styling theme was called "Spirit of Motion," which was essentially adding a thrusting front end onto an otherwise ordinary late-1930s body from the cowling on back.
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Now for some current sedan styling...
Here we find the cliché creases and folds along the lower body. Most stylists pay more attention to sculpting located towards the top of the fender line. Here, effort is made to present a signature shape that, it is hoped, viewers will associate with the brand.
This Hyundai features a rising character line (a speed line, really) that merges into the tail light assembly and trunk.
Impala's sculpting is more elaborate. In addition to folds and creases along the upper and lower areas of the fenders, GM stylists added a character line above the rear wheel opening that's suggestive of a separate rear fender. This evokes details from previous Impala generations.
All that and more characterize this Mercedes. Character (speed) lines slash, wheel openings bulge, and a fold along the top of the front bumper rises and then disappears. All visually dynamic, mind you, but there is a lot of clutter as well.