Its interesting to compare the "old" philosophy. In the A109 power, the limiter is always operating, UNLESS you press the "limit override" button, which is diametrically opposite to what you have on a A139.
I was working with a Mexican customer over the last few days, who operates in an environment with a pressure altitude of 8-12,000', at temperatures of approx ISA +20.
Performance is absolutely critical, because an engine out in these conditions is a massively different kettle of fish to the relatively benign environment we have in Europe for example. This company has changed their SOP to require pilots always to fly with the limit override active, having identified several accidents in the past 18 months which have had running out of power as a contributory or primary factor.
We practised in the FFS with and without the limit override, and of course you may completely trash the engines by using every drop of power you can get, but its is surprising what situations you can fly away from, which you couldn't in the "normal" condition.