Hi ConPollos,
Yes, I am well-aware of the oil/sulphur mixture. I keep a 25 litres drum of oil (acquired from a well-known Shire breeder who has a side-line in selling "Shire Oil" for feathered legs) to which I add sulphur as needed. There's also a product called "Pig Oil," which can be bought...
My anecdotal evidence: I have NEVER had a case of scaly leg since I started using DE in my hens' coop and nest boxes three and a half years ago.
The birds I had in the past had me struggling with their scaly legs. When I built a new hen house and nest boxes (after the last of my old hens...