I agree about lack of docs Rated 3 out of 5 stars
I haven't gotten this thing to work yet because there is no documentation. So I agree with the previous comment about there being a lack of docs. Perhaps using this tool is really obvious for some, but I'm not figuring it out.
I could, howvever, view the jiffy tab in firebug while on the example page, and that looks excellent. So my review is based on that (minus 2 stars for the lack of docs).