“Allow tables to extend into margins” is a Microsoft Word property that I have recently discovered and has the potential of addressing a lot of formatting issues with large (wide) tables.
You can access this property from File->Options->Advanced under the compatibility options. The location is slightly misleading as you’d expect the properties here apply to the Word installation but that’s not the case, many are actually document properties.
This property is disabled for newly created documents but old ones have it enabled which I assume it’s done for compatibility reasons. With this property disabled Microsoft Word will use a different algorithm when resizing tables, one in which the page widths acts as a soft cap for the table width. From what I observed Word uses more aggressive column resize algorithm which includes breaking cell content in the middle of words.
NOTE: the page width is finite so you can craft very large tables for which the columns will be resized beyond the point they are usable ( i.e. 1 character per column).
The RPE test is really simple: generate a document ( in .doc format) that contains a large table that overflow the page borders. Then generate it again but this time use the attached stylesheet and this time you will notice that the table fits the page margins. The example stylesheet is attached: emptyStylesheet
“Allow tables to extend into margins” is in a way a smart document level version of the table’s “autofit to content” property. The advantage is that it is global and that it kicks in only as needed.