One irritation of a hotel stay is having to crawl out of bed to turn off the master switch by the door then stumble back in darkness - a hazard of increasingly sophisticated but unfathomable lighting systems.
If only I had clocked the "sleep" button which dims all the lights from a bedside console when I was shown to my room, my stay would have been pretty well perfect.
You certainly can't beat waking up to a bay window view of Green Park, which the hotel rightly points out is an extension of its fitness facilities. Later, trying, and failing, to find TV channels on the gym treadmill, I wish I had chosen that much more pleasant option.
The rooms are brighter and more contemporary and chic than many of its neighbours, and those bay windows look as though they were once balconies, gorgeous vantage points from which to enjoy the view over Piccadilly's greenery.
Beds are supremely comfortable, and complimentary water, juice, snacks and fresh milk for coffee from the in-room Nespresso machine is welcome. Ditto the free wi-fi.
Bathrooms are a bit pokey and the over-bath showers could do with an update, but the great filter coffee at breakfast made up for the savage shower, compared to the undrinkably weak brew sampled recently at two other of the capital's five-star hotels.
It was good to see eggs florentine on the breakfast menu, but the eggs were spoiled by the residue of overly vinegary poaching water. The standard of lunch and dinner fare, however, makes the hotel a dining destination in its own right.
What distinguishes the place, though, is the exceptionally friendly and personal service. In fact, when the tall, flamboyant silver fox who is a house treasure booms: "welcome home!", seizing your suitcase as you walk in the door, you feel this is your personal Mayfair pied a terre.
Just remember to familiarise yourself with how the lights work before you let the bellboy go.
Rates: Rooms from £260, www.athenaeumhotel.com
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