We are splitting hairs I would suggest!
Whether it was under taxi out (it wasn't - there were no pax on board) or an earlier problem, it is still a tech problem!!
Incidentally, high power runs are now undertaken at D1 or in the loop for these larger aircraft dependant on wind direction. Options for high power runs on the apron are somewhat limited partly due to vehicle / personnel movements and because the car park now surrounds most of stands 19 - 24. The public don't take kindly to having their cars pebble dashed while they are on holiday apparently!!
