OK, so here is the REAL deal.
The A330, when left to it's own devices will start a slow shallow descent from a long way out as this is evidently the most economic way to operate the machine. However,
as long as the pilots are informed of ATC requirements/restrictions prior to the descent point and have time to plan for a faster descent from closer in the aeroplane will happily comply. Increasing speed once the descent has commenced means either pushing the nose down and increasing the ROD, which ultimatly gets you low on profile or increasing power (and burning fuel) to maintain the current ROD whilst accelerating.
Then, throw in 10-15 knots on the tail until 1000' onto 12L and things get REALLY interesting!
