found that if you include blanket at the top, it fails without error message (even with the debug flag on) in both FF and Chrome. by comparing to http://blanketjs.org/examples/backbone-koans-qunit/index.html?coverage=true step-by-step, i found out what i was doing wrong. maybe worth mentioning in the instructions in case more people maybe the same noob error :)
In addition to the grand total already available on the last line of the report, this change allows a user to specify a regular expression which describes how modules are named in your application file structure. When provided, the QUnit reporter also outputs the per-module totals in addition to the grand total.