On an overcoat or peacoat, a double-breasted style can serve to keep the wind out. It can make a significant difference as to whether you stay warm and dry.
But on a suit jacket, the traditional role of a double-breasted style is to waste fabric and buttons. The first purpose of the double-breast is to express a certain decadence, to say that one prefers to have more…
A double-breasted jacket stands opposed to puritanism and Protestant simplicity. Throughout history, the double-breasted jacket has served to symbolize the aristocrat, the decadent artist, the well-off gentleman and the “greed is good” Wall Street banker.
A secondary use of the double-breasted style is that of bringing to mind military dress.
Much military clothing over the last several centuries has been double-breasted, partially, no doubt, because of the desire to stay warm in the elements, and partially because a double-breasted style is ideal for showing off extra rows of brass buttons, braid, and medals.
Double-breasted styles go in and out of fashion depending on the spirit of the age. The more austere and modern the prevailing spirit, the more the double-breasted style seems conservative, wasteful, unnecessary. But the more decadent the spirit, the more that the style charms, feeling more luxuriant, rich, and manly.
The double-breasted style, with a few tweaks, can transform from a Mod look to an Edwardian look. And from the dress of a poet, to that of a banker.
The single-breasted style needs no such introduction, of course. It doesn’t require an explanation the way that a double-breasted jacket does.
As the single-breasted style is the most standard jacket style, it is more flexible. The hem can be shaped from crisp and straight to youthful and cut away.
No doubt most customers will always prefer a single breasted jacket simply because it is less remarkable. Particularly so long as the age is one that values function and clean lines.