UCM is famous for it's extra parameters you can add to the URL to do different things. You can add &IsJava=1 to get all of the local data and result set information that comes back from the idc_service. You can add &IsSoap=1 and get back a SOAP message with that information. Or &IsJson=1 will send it in JSON format. There are ones that change the display like &coreContentOnly=1 which will hide the footer and navigation on the page.
In 10g, you could add &ScriptDebugTrace=1 and it would display the list of resources that were called through includes or eval functions at the bottom of the page. And it would list them in nested order so you could see the order in which they were called and which components overrode each other.
But in 11g, that parameter flag no longer works. Instead, you get a much more powerful one called &IsPageDebug=1. When you add that to a page, you get a small gray tab at the bottom right-hand part of the browser window. When you click it, it will expand and let you choose several pieces of information to display. You can select 'idocscript trace' and display the nested includes you used to get with ScriptDebugTrace.
You can select 'initial binder' and see the local data and result sets coming back from the service, just as you would with IsJava. But in this display, it formats the results in easy to read tables (instead of raw HDA format).
Then you can get the final binder which would contain all of the local data and result sets after executing all of the includes for the display of the page (and not just from the Service call). And then a 'javascript log' for reporting on the javascript functions and times being executed on the page.
Together, these new data displays make page debugging much easier in 11g.
*Note: This post also applies to Universal Records Management (URM).