321 -- Pigs in blankets are traditional for Christmas? Don't remember that on the Cratchits' table.

Bob Scratchit had them in reserve - he let out a massive sigh when no one requested them....

Good God. Worse than I thought. In the US, "pigs in blankets" are frankfurters wrapped in a biscuit dough (US biscuit = baking powder bread, not sweet). When Homer Simpson tells Bart to "Bacon up that sausage, boy!" (wrap it in streaky bacon, in the Simpson family manner), it's meant as a joke. (To clarify: Homer doesn't mean it as a joke; the writers, who are trying to come up with the least healthy food they can think of, do.) Even weirder as an accompaniment to a roast. And with meatballs to wash it all down.
Although given the bread content of English sausages, increasing the meat-to-bread ratio may make more sense than it would here.
One of our guests - best friend for 40 years has just emailed "I will buy the meat" - mmmumph, perhaps she should buy the liquer? Only one cook in this kitchen.
Lamb is an excellent choice for Christmas, although of course in France we serve it with flageolets and lots and lots (and lots) or garlic and parsley.
The surprise would probably be on you if you served Kobe beef -- spending all that money on it and just having your guests say "this tastes weird."
I was served prawns in (bacon) blankets once in Florida. God what a horrible experience that was, not being able to tear the bacon off the shrimp because the hostess was observing my 'enjoyment'.

Ian, small suggestion. Instead of traditional mint sauce, try this. Lots of mint chopped, sugar and lemon juice. Not a sauce but a relish. It gives the mint taste and the slight acidity you want with lamb - but it doesn't ruin your wine. Lamb goes with lots of red wines. A good red Bordeaux is a classic.