During an editing session yesterday, Word slowed to a crawl, sometimes pausing with the spinning wheel for 20-30 seconds before resuming. Right now, I have a document which was 57K in the original version and has ballooned to 161K in the latest revision. I track changes and add comments liberally, and save the docs in compatible mode so there will be no issues with the author or other editors being able to read them. I edit translated documents, most of which were prepared in Asian language (Korean & Japanese) Word versions of several generations.