Shoppers,crowding into the West End of Londonyesterday for the start of sales,answered demands fromthe police to use public transportation rather than theircars.They also decided not to invite danger,after thebursting of a bomb in the West End on Christmasevening,by not waiting in line outside the shops.“Iwould have been very worried of what they had.”saidMr Harry Weblin,manager of Liberty’s.Last night the police,which operated a big actionincluding special searches outside the main shops,spoke highly of the common sense of the holiday