I have broken a couple of CVD pins just recently from hitting things on a tight track, I have changed from the standard hardened steel front drive shafts to the Yokomo aluminium shafts so they will flex when I hit anything, so far so good.
It is something I found out by mistake while running a Pro4, I put steel front shafts in and watched the drive gears and shaft couplings self destruct as the shock is transmitted right through the drive train, alloy will flex and absorb some of the shock. The worst is you might bend or twist a shaft, but you can keep racing.
BTW, I Qualified 7th and finished 3rd yesterday at the Australian Winter Champs in stock with my BD (beaten by a corally and a FK04) This car made me look better than I was driving most of the day and was running the fastest individaul laps times in most rounds with a not perfect setup.