Ouch. You don't trim for pitch, you trim for AoA. How many units of trim is needed for given AoA? Depends on speed, weight, config and CG position. A330 is long aeroplane with large speed range, so having powerful THS is necessary. I wouldn't suspect Airbus designers of being wasteful and putting too strong THS on their airframe. DP Davies has it all neatly explained.
Clandestino, that wasn't a pitch attitude, it was a trim setting. Sorry if I wasn't clear.
I think my point is that the higher trim settings are rarely used unless the cg is way forward
and the flaps are down. What is the highest trim setting you could encounter in a
clean aircraft within the normal flight envelope?