In a mixing bowl, combine the mayonnaise, mustard, garlic, and oregano. Spread the mayo mixture on 8 pieces of the toasted sandwich rolls. Top each piece with shredded romaine, a slice of tomato, and a strip of bacon. Top 4 of the pieces with ham and the other 4 with turkey. Build each sandwich with a turkey half, a ham half, and top with a final piece of sandwich roll for a tri-level sandwich.
