The grant of planning permission for the London Bridge 'Shard' tower is indeed problematic, as Tom Ball says (AJ 27.11.03), representing as it does gross over-development on a small site in a tightly packed area.
The idea that such a major project, with such wide-ranging implications, cutting across UDP and other established policies, can be approved, very largely on questionable assessments of design quality, is certainly disturbing.
Planning decisions should, as far as possible, be made on objective criteria, minimising subjective assessments. In this respect, the abolition of plot ratio as a criterion during the unlamented regime of Nicholas Ridley and Margaret Thatcher was surely ill-advised. Plot ratio may have led to anomalies on particular sites and to have been a relatively blunt instrument, but at least it was an objective bulwark against over-development. While not precluding the tallest buildings (the NatWest Tower was built under plot ratio constraints), it would tend to discourage them and ensure that there is adequate space around them.
The notion that tall buildings should be tightly clustered is, I believe, a serious mistake. They require space around them.
James Dunnett, London N1