I do see why dews are removed and tails are docked on sporting/herding breeds since they can cause nasty injuries down the line and the healing process can be quite tedious with frequent reinjury.
However, with the Pyrs, like Jewel has mentioned, the foot structure is different as is that of the structure of the dews themselves.
I've scrounged up x-rays of a Pyr's hind dews as opposed to, I believe it's mixed breeds used in a dewclaw genome study.
So we're looking at hind right and hind left, the two bottom pictures. HR and HL are two different dogs. Look how the dew sits out there, particularly the single dew on HL. You can imagine how easily that would be injured as the potential for it being bent backward is large. It could easily be injured trampling through brush or coming through a hard crust of snow forcing the dew upwards unnaturally.
So below is going to be our Pyr hind.
Looking closely to the lefthand side you are going to see the more faint bone structure of the double dews. See how much more firm to the leg the bone sits? And the dews come separate off that bone almost at a perpendicular angle.
I have to say I've definitely seen Ralph use his on steep inclines. At camp coming up hillsides on awkward angles he seems to almost put actual weight on them for more sure footing.
I know it's anecdotal but like Jewel said, the first breeder we talked to (breeding since the 70's) has never had a dew injury and her dogs lived outdoors primarily. Ralph's breeder has never had a dew injury that I've heard of in 30+ years of breeding and was adamant they be left intact, I see now with good reason.
So I totally understand the concern/why the heck do ya leave 'em on? (LOL) kind of thought process as coming from breeds who have them regularly removed to prevent injury.
FWIW we went to an emergency vet (not our normal vet) once when Ralph was a pup after a pretty violent diarrhea episode. This young vet was so perplexed with Ralph's dews that I had to finally say, "They're double dews.. Breed trait." We got an, "Oh.. I've never seen that before.. Pretty sturdy."