It just depends on your personal concept of acceptable. I personally have problems with some of these quick methods and the miscellany of results because of bias edges and then trying to match mismatched bias edges. I have looked at this concept and see lots of potential for difficulties that I would not find acceptable. However, I am thinking of trying the concept by cutting squares on the bias. Then the cuts to make the block would be on the straight of grain-or nearly so. But, that eliminated the possibility of it being quick because you could not use pre-cuts. But, I never use pro-cuts anyway.