Stir 3/4 cup oil, vinegar, lemon juice, honey and Worcestershire sauce in small bowl until honey dissolves. Season with salt and pepper.
Melt 2 tablespoons butter in large pot over medium-high heat. Add half of spinach and sauté until wilted, about 3 minutes. Transfer spinach to medium bowl. Cover. Repeat with remaining 2 tablespoons butter and spinach. Season with salt and pepper.
Heat 1 tablespoon oil in heavy large skillet over medium-high heat. Add fish and cook just until opaque in center and golden, about 3 minutes per side.
Divide spinach among plates. Place fish atop spinach. Spread tapenade over fish. Top with salad. Spoon vinaigrette around fish.
