See the attached, I used the answer from here http://community.tableau.com/thread/123528 with an additional nested table calc because the total for the % of total needs to be computed across the Role rather the Division.
The two extra Grand Totals would need to be done via either separate worksheets or custom SQL to duplicate the data source see http://drawingwithnumbers.artisart.org/customizing-grand-totals-part-1/ and http://drawingwithnumbers.artisart.org/customizing-grand-totals-part-3/, respectively.
While I've done more to figure out ways to hack crosstabs and Excel-like functions into Tableau than most, worksheets like this make my eyes go cross-wise. At the least, I'd suggest separating the counts and the % and putting them together in a dashboard, I put together an example in the attached. At a deeper level, text tables are really only good for looking up exact values, and since you're using a % of total it seems like you want to do some comparison. There are a lot of other ways to visualise this, I put some additional worksheets together for that.
Thanks, Jonathan! I really appreciate the feedback and the additional visualizations! My clients requested this very specific table layout but I'll apply the subtotal calc and try to convince them of an alternate view to reflect the % allocation.