My contention on the Krumphau is that it was used in a wide variety of ways and that the description in the text commonly used in the Liechtenauer tradition is only the first way you learn to use a Krumphau.
First, the illustrations of the technique show considerable diversity. From oldest to newest Talhoffer, 1467 shows it here, with crossed hands and the left leg forward and the sword aimed to the left against a the sword of an opponent who seems to be striking or thrusting against you. It is noteworthy that he seems to be striking with the flat or short edge. It's on tafel 19 shown here: http://www.schielhau.org/talpoint.html.
Second, Goliath which is from the early 1500s, has an image which is shown here: http://www.schielhau.org/images/43.jpg. Again to point out, right foot forward, sword on the right side, opponent in left ochs, left foot back and behind, sword on a very high angle from the feet and facing of the striker, hands not crossed and the blow is aimed at the hands.
The third major illustration, found in Meyer which was published a couple of times in the mid 16th c. seems to fit the Liechtenauer text the best. Right foot forward, sword on the left at a strong angle from the line of the feet and the facing of the striker, the opponent, again, is in left ochs. It is shown here with the back figures on the right: http://www.schielhau.org/Meyer.p8.html.
We therefore see the krumphau illustrated on both sides with the right foot forward, on the left with the left foot forward, and possibly with both edges. Now Talhoffer's connection to the Liechtenauer tradition can be disputed, but he certainly seems to have picked up the technique from them. I've employed it as described in Ringeck, and depicted in Talhoffer and see no particular advantage to either one, they both seem to work very well.
As for the Goliath, which is what the OP was asking about. I believe it is wise policy not to assume error on the part of ancient texts lightly. One valid way to view this is that there was a publishing error and they got the wrong picture. This matches the surface evidence but ignores some important points. First, the situation which led up to this sort of major mistake is extremely unlikely. If the subjects had been posing in the position of the text everything about the picture would have been extremely different. It's not the sort of thing where an illustrator would have simply gone home with a pile of half drawn pictures, mixed them up and said "I forgot what that technique looked like so I'll finish the drawing this way cause that's what I think it was". This certainly wouldn't have been the case if the master himself was also his own illustrator, which is very possible. Manuscripts were expensive and produced with far more care than that. An illustrator in that position would simply have asked the author where that particular illustration was supposed to go. Second, the quality of the Goliath illustrator is very good, accurately depicting human proportions, consistently depicting sword length vis-a-vis humans in the book, and adding many non-essential details throughout. Drawing basic body positions is one of the first lessons artists learn, and if they had been posing in the "correct" position he would not have gotten it wrong. Third, there are no marks on that page that indicate obvious errors that an illustrator or later reader might have tried to correct, cover up, or add commentary too as we see in a very few other books from the time. Fourth, there is no other possible technique in the text that this picture might be depicting.
I therefore offer the following hypothesis: the authors intentionally posed as shown for the illustration on the Krumphau page. The implications of this idea are these: The Goliath, by design, depicts a krumphau which does not match the text. Their definition of what a Krumphau was, and how it could be executed, was rather wider than a surface reading of the text might lead us to believe. After all, how else would you interpret "learn to strike blows equally well from both sides" with a krumphau without the kind of variation that we see in the previous three illustrations. I believe that the Goliath illustration is depicting an alternative form of the krumphau which is also designed to hit the hands of an opponent in left ochs. This variation offers a way to strike from your right (strong side for us right handers) effectively if your opponent is strongly covering the upper left quarter, while at the same time covering your upper right quarter, the one normally exposed when executing the krumpahau in the text and the one most easy to hit with a nachreissen or other counter. In my training I have found it effective.
