Interesting discussion. I have a Llewellin setter that does not have her dew claws removed. The breeder does not remove dew claws for the same reasons you discussed above. I have not had problems with injuries to the dew claw, but I do have problems with boots. Whenever I run the dog with boots, she ends up with raw spots on the outside of the dew claw – nothing I do seems to prevent this. I have tried wrapping that area with tape, but the problem persists. I am guessing that the problem is caused by the dew claw slightly protruding, creating a bump that is rubbed by the top of the boot. I have also used several different types of boots with the same problem.
Funny, whenever this happens I cuss the breeder for not removing the dew claws. And I was always skeptical of his list of reasons for not removing the dew claws. But after reading your post and the article from the veterinarian, it looks like he may be right. And maybe it is worth dealing with this minor issue in order to obtain the other benefits of not removing the dew claw. I would be interested if anybody else has this problem, and if they have figured out a solution.
Ray