ekc,
First off, I LOVE renaissance faire-jacobite-pirate shirts with big poofy sleeves*.
Second, I advise the sweater. Everything has it's place and those Highlander (Jacobite) shirts would be too theatrical for a simple Christmas supper. It would make you appear to be wearing a costume instead of clothes.
Go with a sweater and maybe a nice tie (you never get a second chance to make a first impression).
Save your romantic finery for a highland games, a renaissance faire, scottish country dancing, or other times where it will be better appreciated.
Cheers
* I watched WAAAAAAAY too many swashbuckler movies as a child
-See it there, a white plume
Over the battle - A diamond in the ash
Of the ultimate combustion-My panache
Edmond Rostand
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