2.1.1819 Part 4 Section, dispDef (Use Display Math Defaults)

a.   The standard does not specify any effect of the dispDef element.

If dispDef is off, Word ignores the following math elements:  defJc, lMargin, rMargin, wrapRight, and wrapIndent.  When these elements are ignored, Word will use the properties that are specified by the paragraph settings.