It is possible that it is not displaying the text due to the fact that the content is nested in a table. The browser will not render anything until it has closed out the table, no matter what setting you are using for the output cache. If the running of that query is holding up the creation of any html on your page, it could be causing the problem you are experiencing. Since the Portal houses everything in nested tables, perhaps you could use an intermediate page to display a friendly message. Once the query is done, slap the data into a cache object, send the user to the results display page, and load the data from the cache.