f it was indeed made this way and can only fit the pommel one way, it would be a rare one indeed. however, the photo of it's pre-restoration shows a straight tang and the other photos show a round hole in the grip.
Kronckew, I most likely have not seen as many of these disassembled as you have, but on everyone I have handled personally the blades tang would only fit into the hilt one way (where everything, blade, guard and hilt lined up properly) unless being forced. Here is a link to a gunong that I restored: http://www.vikingsword.com/vb/showt...ighlight=gunong
You will see that just like the blade on the one Jose restored that there is a slight curve in the tang (opposite direction from Detlefs) and that the tang socket in the hilt itself looks to be mostly round (again like the one we are discussing) but the tang would only fit into the socket one way where everything would line up properly. As I personally did not do the restoration on Detlefs gunong I can only express my confidence in Jose and say that if the blade would have fit into the hilt on what is accepted as the normal direction (blade tip facing downwards) that he would have placed it that way.