We've used the example iDashboards.aspx file to put dashboards on the initial page in Staff Web View after login. It looks fine in 15.1.2 (BlueWave theme) -- the dashboards occupy everything below the module tabs at the top down to the print and email buttons at the bottom.
We upgraded to 15.1.3. The BlueWave-based theme still looks fine. As an experiment, I applied the UltraWave theme. The site looks OK in IE8, but in Firefox the dashboards are only about 150 pixels tall. This is strange, because the non-script part of the example is simply: