Music is added to movies last, and changing it has always been difficult. But the composer of the much-anticipated remake of “King Kong” has been removed just weeks before the film opens. How? “New technology has meant that composers can now be asked to present their score in a demo form on synthesisers before its been properly recorded. They then ask test audiences what they think. It is like judging a film by having the cast shout out the script first. People have been taken off films on the basis of the results. It is not a particularly rational form of decision-making.”