This comment is for the Text import, not the XML or VCARD portion, but it notes an interesting limitation.
Text import only allows ONE event of any Type per Person row of import.
It allows multiple Event columns per row (Birth, Baptism, Occupation, Residence, Death, Burial)… but only one instance of each type per Row.
But you can add additional Person rows that reference the same Person ID (all the name fields can remain NULL to simplify input) for each additional Event of that type.