I'm not sure what is being referred to the images, but the tangs were forged too cold due to the "I" beam type cross section. This happens with every single new forging student I have seen. I have a soapstone test that I use in my classes where I swipe the flat of the stone down the side of students blades and if the blade has a white outline they need to get the steel hotter and flatten the work out better. But this is not necessarily bad for the steel, it just makes for a bad forging. If over-done it can lead to black stress lines running down the center of the forging.