Not necessarily, they wouldn't need to add anything (above ref plus +5) if they were using autothrottle.
PJ2:
According to Boeing procedures for the 777, speed additives are only required when using manual thrust. If the autothrust is engaged, which it normally is, then the MCP command window is set to Vref+5.
From the Boeing Flight Crew Training Manual for the 777: "Sufficient wind and gust protection is available with the auto-thrust engaged because the auto-thrust is designed to adjust thrust rapidly when the airspeed drops below command speed while reducing thrust slowly when the airspeed exceeds command speed. In turbulence, the result is that average thrust is higher than necessary to maintain command speed. This results in an average speed exceeding command speed."