I see an additional problem: The attribute style:master-page-break (19.497) has the text, "This attribute is ignored if it is associated with a paragraph style that is applied to a paragraph within a table." But the descriptions for fo:break-before (20.178) and fo:break-after (20.177) do not contain such restriction.
Allowing a page-break within one table-cell would cause a lot of further rules, what to do with the other cells on the same row. I suggest to add for fo:break-before and fo:break-after too, that this attribute is ignored for a paragraph inside a table cell.
It is possible to set a fo:break-before or fo:break-after as attribute of a table-row. That should be sufficient to describe how tables are distributed on several pages.
I think Jos and Patrick made the right conclusion and found the right links to the specification.