This dish is near to Steve's heart. He makes it often with the briny oysters raised in Katama Bay, close to his home on Martha's Vineyard. If your experience with smoked oysters is limited to the oily, strong-flavored bivalves sold canned, you're in for a revelation. The brininess of the olive- and caper-laced relish echoes the fresh, oceany notes of the oysters. Keep as much of the oysters' juices as possible in the shells while shucking and grilling.