I am currently evaluating Dojo, YUI and jQuery. One thing I notice with Dojo that doesn't sit that well with me is the use of custom HTML attributes. Using custom attributes causes problems with validation.
Instead of using dojoType="dijit.layout.AccordionContainer" what is wrong with attaching via CSS class or ID in the javascript. Eg. dojo.setType(document.getElementById('accord'), 'dijit.layout.AccordionContainer');
you can use (in 1.1)
you can use (in 1.1) NodeList.instantiate:
say your accordion (before having a dojoType attrib) has id="bar"
dojo.query("#bar").instantiate(dijit.layout.AccordionPane,{ /* properties like */ title:"heading" });