Your post sounds like a joke but...there is some truth in it!
As i noticed for my experience (and not only for citruses but in general for all fruit trees) there are 2 conditions that "force" a tree to flower and bear early:
A- the tree is growing in an IDEAL environment with perfect combination of soil/water/climatic conditions/fertilizing etc...in this case tree will thrive and will reach quite quickly an adequate dimension to bear fruits
B- The tree is experience a strong STRESS condition (may it be water deficiency or persts attack or too hot/cold temperatures) something really putting so much pressure on it and undermining even its own existence.
Well in many of these cases the tree will be more prone to flower and bear fruits, it's like an evolutionist urgency to reproduce before the worst might happen.
Well I think your pomelo experienced this kind of B condition while mine is growing in a confortable condition that's why it has no urgency to reproduce now since it can still grow easily :-)