Do you think nutrition has anything to do with this? Both my coco cream trees (which came from the 2011 batch) produced poorly until this year -- which is the first year that I've really taken care of their nutritional needs with plenty of micros, p and k, starting a year before the bloom. My pina colada is doing the same thing -- it's loaded with bb's... as are all of my trees.
The party line among mango tree growers seems to be that they don't need anything but potassium. But, I've found that to be untrue. It is indeed true that mangoes do exceptionally well in the absence of nitrogen, but they do need micros, p and k.
another year of super heavy bloom on coconut cream, another year with 2 or so bb sized fruit when all is said and done.
They are erratic, unreliable fruiters due to a tendency towards bad ratios of male flowers some years.