Approachable luxury at one of London&rsquos best addresses&rsquo proclaim a competing hotel&rsquos billboards as you walk down Park Lane towards the Dorchester. &lsquoApproachable&rsquo seems a good tack to take, since &lsquoaffordable&rsquo can hardly be allowed to oxymoronify &lsquoluxury&rsquo. Indeed, there are plenty of clues that you are not only approaching luxury but already engulfed by it as you pass the Aston Martin, the Corvette and Cadillac, and then the huge upper-end BMW showrooms. The day is beautiful, sunny at the moment, but promising proper summer heat later. The Dorchester is undergoing refurbishment and has its own billboard over a side-entrance being renovated. In the picture, there&rsquos a bald man in chef kit and he seems to be dragging himself away from a pretty woman in a flimsy evening dress who has draped herself around one of his knees the text says &ldquoAiden Byrne is now at The Grill. And yes, he is proving rather popular.&rdquo