Holding each lobster tail shell side down, cut away the ribbed membrane as close to the shell as possible with kitchen shears, remove the lobster meat in one piece from each shell, and rinse and pat dry the shells.
Devein the pieces of lobster meat if necessary, rinse and pat them dry, and sprinkle them with the lemon juice.
In a small saucepan melt the butter with minced garlic and remove the pan from the heat.
In a shallow bowl stir together well the bread crumbs, the salt, the pepper, the herbs, the garlic powder, the cayenne and the Parmesan cheese.
Roll the pieces of lobster meat in the garlic butter, dredge them in the bread crumb mixture and return them to the shells.
Grill the lobster tails, shell sides down, on a rack set 4-6-inches over glowing coals, turning them occasionally from side to side, for 10 minutes.
Cover the grill and grill the lobster tails for 5-10 minutes more, or until they are just cooked through.