I’ve ranted a few times about the many reasons I dislike the use of steamers on tailored clothing, but one of the reasons which I failed to fully explain was ironwork. Tailors use heat and steam to transform a flat piece of cloth into a 3-dimensional shape, only some of which occurs due to seams and darts, the rest is worked up with the iron (thus, ironwork).
Here’s a look at what goes into the jacket before a single stitch is sewn; the trousers get worked up as well, which I alluded to in a previous post somewhere. The pages are nicked from an old textbook entitled (somewhat pompously) Il Sarto Architetto (The Tailor as Architect) and those who can’t read Italian will still be able to get an idea of what’s going on here. Namely, that a lot of shaping is being done which can be ruined with the aid of a jiffy steamer. You wouldn’t notice anything jumping out at you, but the garment just wouldn’t have the same shape or fit as before; very fitted or shapely (men’s) garments are impossible to achieve without a good deal of this ironwork- something looser or more boxy will have less of it.
Cross-hatch lines indicate stretching and curved lines indicate shrinking.