Word 2003 Open has taken 10 seconds for years with a doc; now is 1 minute; what is it doing?

Any idea on how to troubleshoot a super-long loading time?

I have Visual Studio 2017 loaded, if there's any way to debug it with that.  (I'm a C++ programmer).

On Unix I'd use the strace or truss utility to track system calls and see which ones are taking a long time.

The document has one template with several dozen styles, a few macros, custom toolbars.  The document is about 125 pages.  That said, it loaded quite quickly until a few months ago I think.  

I'd much appreciate any ideas on this!