Hi Greg,
It is good actually. Tried it out. If you have it on for a session, it gives a nice report on all that has written to your hard disk, even things you weren't aware off, so you can look into these. Could be usefull more as an evaluation tool. You can also save the reports for comparison later as I do with my leak monitor reports.
Just like your HD, also your browser has a "secret life". Just imagine what "nsPrefBranchgetSocPref, history.wrapper.js anonymous"does on a load up of a page even with NoScript on 80 instances on line 62 of this webforum here alone. Amazing!
polonus