Matrix Reporting: broken if saved?

I'm seeing some very weird behavior on a matrix report.  I'm having trouble believing that what I'm seeing is really how things are supposed to work. 

So here's the situation: I want a crosstab that will show me hours worked by employee by job.  I've got employees as columns, job names as rows and duration as the value.

If I create a new report and press the "Run Report" button, it works exactly as I want it to.  One row per job and a sum of hours worked per employee. If multiple employees worked a job, it shows up as multiple values in the appropriate row. Awesome.