My pal says you can get it hot rolled on a plate mill, flatten it, and then treat it. As far as stress reliving the post machining, I don't see why not. Have you googled it and looked through tutorials? It seems like there's a video for just about anything on YouTube. Good luck.
I agree that the explanation doesn't seem totally sufficient. There are several things that can go wrong in each scenario, but you would think more measures would be taken to keep both ends of cable B from breaking with different tensions. Interesting thread- I hope an expert comments!