It seems to me like they all broke bud dormancy at the same time.
Some plants had 100% of their buds as fruit buds, others had 50% of their buds as fruit/flower buds and another probably had only 5% of the buds as fruit buds and the rest as leave buds.
Do a google search on flower bud vs leaf bud.
Maybe you pruned the others ones more so they put on more vegetative growth (waterspout).
Maybe this one is thicker/older/mature so it is at that age where it produces.
This plant might be one that fruits alot
in year 1 and then none in year 2 where it saves up alot of sugar and then fruits alot in year 3, even though it is the same cultivar.
Maybe this plant is being stressed alot (pest, copper nail?, etc) so it thinks it is going to die and puts all its energy
into a last ditch plan to create some offspring.
Or this plant could have an abundance of nutrients and thus had amble to but into flower production.
If the plants has more flower than it can supply sugar to, the plant will produce less the next year, and it will create a vicious cycle so it is best to prevent some of the fruits from developing too far. Less than 3 weeks. Normally the tree will drop alot of what it cannot handle or are malformed (not pollinated, etc)