I hadn't known that Alec Guinness played Hitler in the Bunker

The script is very similar to the one used in all the parodies.



Very similar indeed.  This is the original with subtitles, not a parody.



Guinness plays the role with a less passionate outburst than Bruno Ganz, and the contrast is pretty interesting.  It may say less about the actors than how the style of films changed between 1973 and 2004.

Hitler: The Last Ten Days vs. Der Untergang.  It's not a cage match, it's a Fuhrerbunker match!