Well there's a lack of information on which to comment any further.
The pictures for the Murks 3 and 3.1 can be find linked to in the "Gallerie" section of the respective sections on this page:
http://watercoolplanet.de/index.php?open=4&show=2
nov1c3, the Kaltmacher thread linked to is full of discussion by the German enthusiasts over the accuracy of the testbed.
All I can say is that the results of the Murks 3, from what I saw of its pictures and description, were about what I expected. To then achieve >4C gain on top of that, is in my mind, nigh on totally unbelievable. I'm not saying that it absolutely is not possible, that would be silly, but right now my level of doubt is bordering on extreme.
Tommy, also I had asked if another testbed had verified the size of the difference between the Murks 3 and 3.1.