Prepare linguine as label directs, but do not use salt in water; drain. Meanwhile, cut chicken into 1/2-inch-wide strips. Slice pea pods, endive, and radicchio into thin strips. Cut garlic clove in half. In nonstick 12-inch skillet over medium heat, in 1 tablespoon hot salad oil, cook garlic until golden brown. With slotted spoon, discard garlic. In oil in skillet over medium-high heat, cook chicken strips until chicken just loses its pink color throughout. With slotted spoon, remove chicken to plate. To drippings in skillet, add pea pods and bean sprouts and cook until vegetables are tender-crisp and lightly browned. Remove vegetables to plate with chicken. In cup, with fork, mix soy sauce, vinegar, mustard, sugar, and 1 tablespoon salad oil until blended. To serve, arrange endive, radicchio, and watercress around rim of 6 dinner plates. Place linguine and pea-pod mixture in center; top with chicken. Drizzle with mustard vinaigrette; toss to serve.