Interesting about procedure/holding speeds. Some years ago was approaching LHR and was advised that they were in the process of changing runways and to remain at cruise altitude (FL370) and hold at LOGAN as published. LOGAN at that time was left turns at max 210 knots. Informed the controller that 210 knots for us was not possible and requested a higher speed.
His response was, '...hold as published'.
Really don't think he had ANY idea that heavy jets (or indeed any jet) need higher IAS for holding at flight levels.