This is a pretty difficult one and while I personally don't like to pummel someone with rib fractures in my experience it comes down to what is going to be MOST harmful - pounding a chest with rib fractures or allowing secretions to remain in the lungs. As a senior once said to me - there's no point saving someone's ribs if they're going to drown in their own secretions.

So ultimately I think it's a personal choice that needs to be backed with sound clinical judgement.

Ray