2.1.535 Part 1 Section 17.18.15, ST_DocPartBehavior (Insertion Behavior Types)

a.   The standard says that when the behavior is set to pg, the entry is preceded by a blank paragraph whose only content is a page break character.

In Word, when the behavior is set to pg, the entry is preceded by a page break character, but that page break character is not necessarily the only content in the previous paragraph.

b.   The standard says that when the behavior is set to pg, the entry is put on its own new page by preceding it with a page break.

In Word, when the behavior is set to pg, the entry is put on its own new page by adding a preceding and trailing page break.