A family of Microsoft word processing software products for creating web, email, and print documents.
I tried this. It worked for a while and then saving took ages again. The only workaround that works for me is to disable background saves.
Here's what I found:
Original document with sections, footnotes, graphics and 500 pages of text saved from Word 2010, 1.51Mb in size
Save times
Saved in Word 2010 and 2013 compatability mode - 20 seconds
Document converted from 'compatability mode' to 2013 format - 2 minutes 30 seconds
Copied and pasted into a blank 2013 document - 33 seconds
Copied and pasted document with background saving turned off - 6 seconds
To turn off background saves use File > Options > Advanced > scroll to 'save' section and remove the check next to 'Allow background saves'.
Beware of the last option - turning off background saves - You'll have to save manually and it may cost you a lost document.