Yes, initially. Soften the callous with daily application, and in time you will be able to remove layers of dead, hard skin. In time, the calloused area will become smaller and smaller. With some dogs, even the fur can grow back, but it is depensive on:
Whether one can keep it up, day in and day out.
Finding the product that works for your dog.
Not using human callous/corn products which are poisonous to dogs, as they can lick the stuff, we can't!
How advanced the callouses already are - ie: how deep, how dry and how large etc.
The hardest one of all, trying to keep a dog from lying on hard surfaces whilst being treated. That is easier said than done, as treatment can take an awfully long time.
How a dog positions it's body when laying down also has some emphasis on the degree of their callouses.