As we build up to the opening of our Allen Jones exhibition in Burlington Gardens next week, a lone statue has appeared in front of our building.   It looks impressive, hydra-headed, as if it doesn’t know whether to belong to Bond Street or Regent Street.   We have been discussing with a number of local bodies, including Westminster City Council and the New West End Company, how to improve the look-and-feel of the neighbourhood.   One public sculpture shows what a difference a well chosen intervention can make: