I've never seen any corruption on HFS.
Logical fallacy: argument from ignorance.
Pre-journaling, it happened every single time the system was shut down improperly. Journaling has helped a LOT, but it still doesn't *completely* mitigate the issue of corrupt directory structures. BUT journaling is implemented as a hack on top of the existing HFS+. It really is an after-thought, and it works pretty well for a hack.