I used a clumsy work-around at the time, but being able to give them a summary of edits and comments would have been very useful.
Maybe they were simply inexperienced with Track Changes. I wanted my client to see my tracked edits, but they seemed to not see the edits at all, even my comments. Since then, I’ve come across some solutions in Word too.
A few months ago, I wrote about having trouble getting an author to see my tracked changes in Word (and showed a solution for that problem in PDFs).