You'll find conflicting information regarding dogs and bones (cooked, raw, chicken, beef, etc etc). Some vets think they are okay, some don't. It's just like the age old rawhide scenario. EVERY bone has the potential for complications, but more vets see complications with cooked bones versus raw bones. You're not going to find any one answer to your question.
Perhaps the best answer would be to talk to YOUR vet who knows YOUR dog and ask him/her. Some dogs do fine, and, while researching your question, I found that one person who fed her dog the 'right kind' of bone spent tons of money having a piece of bone removed that had lodged in her dog's esophogus.
In general, I found that the larger the dog, the larger the risk because larger dogs are more aggressive chewers which makes them more likely to break a smaller chunk off of a bone and swallow it. Splintering bones or not. Any bone can break into fragments. It's not so much the sharpness of the fragment as it is the size of the fragment and how long the stomach acids take to digest it. Longer digestion leads to intestinal blockage (possibly) Larger fragments, if swallowed, can get stuck in the throat or teeth and some dogs even break teeth on bones.
I give my B rawhide, but I fear bones and won't give them to him. I can't really afford to spend 1000's of dollars on surgery. It's just a risk I prefer not to take.