my question was, had anyone ever repaired one that way.
I have been welding, brazing, and silver soldering all types of metals since the early 1960's, including working as a pipefitter for the world's largest winery in Livingston California, owned by E & J Gallo. I was one of 3 people on a 46-man maintenance crew who specialized in doing cast iron repairs. I would not attempt to do what you are proposing.
Jerry