Since the patent application is presumably in German anyway, I think we'll just take your word for it. I remember just about enough German from high school to ask where the library is and order a sausage and bier. I still think the gas relief was a side benefit, not the original intent, but no biggie either way.
A man that has a thumb cut added has serious Mauser issues! Good for you.
I read once of a man that added the cut to a M70 in .458 to make it easier to load in a tight spot. He used a file, cut it too deep, and had to cycle the bolt carefully to keep from catching the left bolt lug in the hole. Whoops.
