I think this has been asked before, or proposed as an Idea, but I cannot find any old postings on the subject with the 'Search' tool.
Update - I just found this idea : work offline for unified workGroup Manager (e.g. for NX) , so please go and add your up-Votes now !!
The Workgroup Manager is often described as working "exactly the same way" for 3rd party CAD applications, up until somebody points out a difference, and then the usual answer is "PTC don't have control over the 3rd party CAD applications...". I don't find either of these responses particularly convincing as an explanation of why the WGM does not have Offline Workspaces and Portable Workspaces.
Comments ?