I struggled mightily to get the tabs to do what I needed, in general, I didn't want the "layout" features which forced me to have sized tabcontainers. If a tab was loaded via href, I wanted the tabcontainer to extend to the height of whatever got sucked in (ala standard dom behavior). You can do this, but it takes some css tricks. This is how I acheived it.

1.) Pop a doLayout=false on your dijit.layout.TabContainer. Do a style of width:100%;height:100% as well.