I just tried this. It has a lot of overlap with YSlow, but there are some interesting extra rules in it, most notably a rule that finds inefficient CSS selectors. That's kind of cool.
As for your issue, I would hope that if a client is savvy enough to check with these tools, they could also understand when you tell them what is important and what is not.
A good addition would be the Printable Version of the report the way YSlow provides.
On Page Speed Activity tab, it seemed to be all messed up. It did the activity profiling for all pages open currently in the browser and not only for the specific page open in the current tab. Bug ? or did I miss some settings.