Here's a little thought:
I'm not sure exactly how pprune is stored on the server (SQL database?) but would it be possible (mods?) for someone to download a thread directly from the back-end database I.E.
(Ignore the [] they are for ease of reading)
SELECT [Date], [UserName], [PostText] FROM [Thread]
WHERE [Thread] = "Thread Name" AND [UserName] = "mazzy1026"
Or thereabouts
Other than that I have tried every possible way under the sun to save my thread as a readable file (csv, excel, SQL database - even Access) other than go through them all manually and save them to a table individually