On Claghorn's urging, I present to you: not a rule broken per se, but modification on convention, the coat 3 piece.
First got this idea where people talked about wearing a coat but not a jacket to work because of indoor heating in some places, and some people choosing to wear a waistcoat in those situations to keep up some formality (so one can still wear a tie, cover up button area and break between trousers and shirt). So then I thought, why not just wear a three piece where the jacket is coat instead? And I love trenchcoats, so I comissioned this from Luxire, with the benefit being that all the pieces are entirely wearable on their own.
Fabric is Dugdale Caldonaire Tweed. Had them make me a hood for the drizzles, too.
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With hood up, kinda ugly, but hey, function.
Featuring gloves and bag:
With hood attached: the collar lifts up a little, slightly melodramatic I think.