Also the LCY ground staff need to be more vigilant at the gate to ensure that the cabin crew do not end up wasting time having to tag bags for the hold this is time consuming and slows down on time departures.
This would make no difference as this would slow down the processing of passengers through the gate and thus would still cause a delay. This problem is the same the world over, not just LCY. Passengers are more reluctant than ever to check bags in.