The point is that the weld was bad. That's what broke and what caused the crash. No crap a part like that shouldn't have a bad weld. That's what the thread is about. As far As a bad design. Who knows. It may be a good design that just welded bad. Those arms don't need to be gusseted if the proper material was used and welded correctly. Even with a gusset that arm would have broken with a crappy weld like that.
And the point I was making about the stock arm being g cracked is that even though you have stock stuff under there it's not bolt on and forget it.