If you guys really experience that much inconsistency it must be the way the fabrics hang or something. I have about 8 shirts from 2009-2012, short sleeve, long sleeve, dress shirts, casual shirts, a double layer, all different fabrics and collars and shapes and every single one of them measures 16.5" in the shoulders and 19.5" in the chest.
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Similarly, all my jeans (10+) measure 15.5" in the waist and 6.5" at the hem, some fitting tighter through the leg but still mostly the same. (Ash denim and moto jeans on the looser side, all the washed pairs and the solid colors from SS12 fitting tighter) I won't question that there are some different cuts though, like the gross loose light wash from SS12, the tapered buckled ones from FW11 and a raw denim pair I had from a couple years ago. I am getting the feeling that they are going to start being more clear about that ("type B" jeans at Blackbird, "type C" at Anture) so hopefully that will help but still I think you can usually tell pretty easily from fit pics. Gradient jeans from 2010 and Maharadja pants from 2008 fit the same as the current season jeans.
Even the jackets all seemed sized consistently to me, except the obvious like my overcoat fits bigger than my jean jacket because its made to be worn over things and certain things that are supposed to be worn oversized like the fleece blazers and this season's sweatshirts and I think they can look good that way. I tried on the hooded bomber that was on B&S as well as the long black jacket that was with it, I think they were from 2008 and 2010 or something and they pretty much fit just like my green bomber from 2010 and my flight jacket from 2012
Maybe I'm just lucky