Coleridge's Man from Porlock, the unwanted intruder and interrupter of marvels, now has his architectural equivalent in the new Strata Tower, located innocuously (you would think) in South London but actually now visible in several important views of historic buildings. In fact it's so prominent an interloper that it's set fair to become one of the most photographed buildings in London, without ever deliberately being photographed at all. You can see it leering over Southwark Cathedral. It appears in the classic view of Lambeth Palace, otherwise essentially unchanged for centuries and before this a picture of contemplative calm. Not any more. And yes, there it is again, poking up alongside The Palace of Westminster and Westminster Abbey in the long view down the Serpentine. Did anyone consider the wider impact of this building? Were photomontages produced, as the old Royal Fine Art Commission would have insisted? Or was its successor as guardian of aesthetic amenity asleep on the job, or taken in perhaps by the greenwash of wind turbines on the roof (they're going to fill the three holes)? All in all it's an eloquent building. It says, very loud and very clear, that London's tall buildings policy has failed miserably and needs to be rethought. And it also reminds us that the Royal Fine Art Commission, which made it its business to examine the precise impact of proposed buildings on important views, has not been adequately replaced. The new Government could do much worse than to bring it back.