since it cannot be used at the same time as 06/24 it has become generally useless
Nonsense. It was used simultaneously for many years. It used to be a favourite for departures off 12 for south or SE-bound traffic which then didn't have to do the long taxi to hold at A1 or D1 - and those movements could happen simultaneously with any amount of use of 06 or 24.
The current lack of use is because (a) they have deliberately excluded GA and non-CAT big jet movements from all other places to park apart from the end of 30; (b) they don't like the extra ops workload of 2 x runway inspections for relatively few movements and (c) their master plan has always been to close it to make way for much more profitable non-aviation activity.