Yeah right - hold short of runway while the engines are fired up from cold, then move onto runway for immediate application of take-off power - have they factored the reduced engine life into their projected fuel savings!
Have you thought about the possibility of starting the engines when number 2 or 3 for take off?
It is, or was common pratice for 3 or 4 holers to shut 1 or 2 engines down when in an extended queue, then re light when number 2 or 3 for take off.
So, out the window goes that excuse.