This isn’t a question–just an observation about something the Word programmers should fix. It applies to documents that have (1) at least one heading level in all-caps and (2) an automatic table of contents.
You would think it would be efficient to give the all-caps attribute to the Heading style for the heading level that needs to be in all-caps to be sure it always displays that way. Unfortunately, the all-caps attribute doesn’t get transferred to the TOC style, so unless all your headings on that level are actually all-caps, that TOC level won’t automatically be in all-caps. Thus, you shouldn’t use the all-caps attribute in this situation.
In case you’ve never run across this before, I’ve attached a sample document. The Heading 1 style includes the all-caps attribute, so those headings display as all-caps in the body of the document. However, I deliberately did not actually capitalize all letters in those titles to show what happens when the TOC is run. Of course you could add the all-caps attribute to the TOC style to solve the problem, but I think Word should have this built in.