Yes, Sewing School is a Canadian team. We use the metric system and it’s great. But I always sew in inches.
An inch is so nicely broken up into 1/4, 1/8, 1/16 slices, which I think are perfect for sewing. Things like hems, seam allowances, and the width of your fabric all lend themselves well to the inch. It’s just a really nicely divided and easy to work with.
As a graphic designer, when I need precision, I find that centimeters and millimeteres are excellent units. But they just don’t make sense for sewing.
So I will continue to sew in inches even though I tell the temperature in ºC and try to drink a litre of water a day. :)