Because we're not specifying a portlet instance, the portlet will be maximized.
The url must include the ROOT portlet ID (56). (This is required due to the override "templateId" in the 5th URL segment.)
An example URL is:
which places the JournalArticle articleId=WELCOME, groupId=23, using the default template, on the layout /web/guest/home
Override the default template as usual by appending it as an extra URL segment:
You can still target a specific JC portlet by specifying the instance id of the portlet (found in the portlet "Configuration" as "Portlet ID:") rather than the ROOT portlet ID