That Not So Simple Knit Dress: Simplicity 5364 from 1972
We tend to thinks of knits as perfect for very simple garments we simply pull on. The T-shirt, T-shirt dress, leggings, etc. But when knits first became common in women's wear because of innovations in machines that could knit fabric, they were not shown as all that simple. The T-shirt dress showed up in the 1950s and came with the full assortment of accessories including hat and gloves. The synthetic knits which became so popular in the 1960s still had zippers down the backs of the dresses they were made from.
Similarly, this formal evening dress from the early 1970s required a knit fabric, see the "STRETCH" directions on the front that literally stretched out the font. It was not a great deal of stretch, in truth. 4 inches had to stretch to a bit over 5 inches, while we have super stretchy rayon/lycras today that practically double in width when pulled hard. But it was far more stretch than the "bonded knits" which were popular for A-line shapes and had no stretch at all (and not purpose as far as i can see). They especially recommended matte jersey (which would be Quiana in those days), cire jersey (which has a wet look and would have looked sooooo louche), and tricot (which we see today only in lingerie fabrics). But any jersey with stretch from cotton to rayon to polyester or nylon was approved.
With only a bit of stretch built into the fabric, the pattern, which was close fitting, has shaped front and back pieces and back straps. It shuts at the back neck with buttons and loops while a zipper shuts the back bodice and then the top of the long gathered skirt.
It gives you an idea of how formal an evening gown could still look in the 1970s even after the Youth Quake revolution in fashion which claimed there should be no rules of any kind of clothing. But people still liked to dress up, so they never gave up on formality entirely.