Bring large pot of water to boil. Add lobsters; cover and boil 9 minutes. Using tongs, transfer lobsters to large bowl of cole water. Reserve 4 cups cooking liquid. Drain lobsters. Working over bowl to collect juices, remove claws and tails. Cut tail meat through shells into 1/2 inch wide medallions. Remove shells. Crack claws; carefully remove meat. Reserve large pieces, reserving all juices and shells.
Melt 1 tablespoon butter in heavy large saucepan over medium heat. Add onion, curry and garlic, saute 2 minutes. Stir in tomato juices. Boil mixture 2 minutes. Stir in tomato paste, then Calvados and reserved shells and juices. Boil mixture 2 minutes. Add reserved 4 cups lobster cooking liquid, wine, thyme, parsley and bay leaf; bring to boil. Reduce heat; simmer until sauce is reduced to 1 2/3 cups, about 45 minutes. Strain into medium skillet, discarding solids. (Can be prepared 6 hours ahead. Cover; shill lobster and sauce.)
Mix 2 tablespoons butter and flour in small bowl. Bring sauce to simmer. Whisk in butter mixture; boil 2 minutes, whisking constantly. Season with salt and pepper.
Melt 1 tablespoon butter in another heavy medium skillet over medium heat. Add lobster medallions and claw meat. Saute just until heated through, about 1 minute. Divide sauce among 4 plates. Arrange medallions and claw meat atop sauce and serve.
This will make either 4 appetizer servings or 2 main course servings.