This week I've been working on a piece of clothing, a 1950s reissue from about 4 years ago, Simplicity 3673.
It came together really well, and I had a perfect dress. Except I had one a size too small. Zip won't do up.
Why? Vanity sizing. A 12, 14, or 16 in the 1950s now equates to a 10, 12, or 14 in 2014. You sell more clothes if people trying them on think they're a size smaller, so manufacturers have shifted the sizes upwards over the decades. And I didn't check the feet-and-inches(Dressmaking's not like engineering folks!) before cutting, so ended up with a 1950s sized garment. Modern Simplicity clothing fits me at the right size, this one didn't.
We can all cock up our measurements whether we're making spacecraft or clothing. But at least a millimeter from the '50s is the still a thousandth of a metre in 2014.
(This post was first made a couple of days ago to my local hackspace list. I'm not the only one hereabouts afflicted with the delusion that they can make clothing.)