[ischmitz]

Whenever I’ve seen burned traces they were caused by overload rather than cracked joints. So it’s highly unlikely.

The trace is slimmest in the center between the joints and that’s where the heat is the greatest. A cracked joint either welds shut due to heat or opens up completely to the point where it doesn’t conduct enough current to heat the gap.

In either case there it wouldn’t produce sufficient heat to burn the entire trace like in your image. This was prolonged exposure to over current.

Cheers,
Ingo