Hi:
The use of _webout and the content-type header that you have in your data step program are techniques meant to be used with ONLY streaming output -- primarily web-based output. (EG does not produce web-based output -- at least not in the same way as the Information Delivery Portal.)
I am only aware of the ability to use TAGSETS.EXCELXP with the Information Delivery Portal -- not EG, not the SAS Add-In, not WRS. When you force streaming to transient in EG, you are telling EG that it's OK for the stored process to make a temporary package and return the package to the client app. The transient result type in EG is generally used for returning both text and graph output from a single stored process. Transient results do NOT use a content-type header or _webout. _WEBOUT is like a pipeline between a web server and the client application. Streaming results are the only type of results that usually go down that pipeline. If transient results go down that pipeline, they do not need a content-type header -- because they are already "packaged" to go to a temporary Internet cache location where the receiving client application knows how to get them.
But consider some other facts about stored processes....you could -try- to return HTML or PDF results from a stored process (for example) to PowerPoint -- but that stored process would not work because PowerPoint can ONLY receive SASReport XML results from a stored process, so behind the scenes, those result types are usually converted to SASReport XML (unless, you specified an HTML or PDF option in your SP, in which case, you'd just get an error message.)
---Web Report Studio can ONLY receive SASReport XML results from a stored process.
--Microsoft Word can only receive HTML, RTF or SASReport XML results from a stored process.
--Microsoft Excel can only receive HTML, CSV or SASReport XML from a stored process.
--EG can only receive HTML, RTF, PDF or SASReport XML results from a stored process.
--Information Deliver Portal -- because of its ability to handle streaming output using _WEBOUT, and the ability to change the content-type header, the IDP can receive just about any kind of results, as long as the content-type header is correct and the receiving system has the application referenced in the content-type header. I have successfully used a technique such as yours with a stored process that ran in the IDP.
You might want to check with Tech Support to see whether the above still holds true for SAS 9.2. All my experience with ExcelXP was in the SAS/BI 9.1.3 world, I don't have a 9.2 image to play with.
cynthia